David Randall; Tamara Marshall, in Her Individual Capacity and in Her Capacity As Parent and Custodian of Shanequia Marshall, a Minor; Jerry Vance; Edward Jones; Dana Williams; Yolanda Hamlet; Jerry L. Swint; Carlos R. Marshall; Jason P. Mobley; Jermaine E. Mayhew; Stephen J. Mcabee, Plaintiffs-appellees, and John Williams; Eloise Jones; Francine C. Williams, Plaintiffs, v. Prince George's County, Maryland; James M. Silvers, Corporal; David Rosser, Corporal, Id # 1784; Stephan Ricker, Detective, # 706, Retired; F. Michael Mcquillan, Lieutenant, # 521; George A. Swope, Sergeant, # 878, Defendants-appellants, and Wayne Curry, Individually and in His Official Capacity; John Farrell, Chief, in His Official Capacity; Alphonso Hawkins, Individually and in His Official Capacity; Kenneth Bailey, Detective; Darrin Palmer, Detective; Prince George's County Police Department; Harry W. Oldfield, Iii, Pofc, Id # 2025; Steven M. Kerpelman, Corporal, Id # 1123; Colleen Mallon, Corporal, # 1499; Shirley L. Mccaffrey, Corporal, # 1221; Andrew K. Rositch, Corporal, # 1264; Keith A. Harmon, # 688, Retired; Joseph R. Hoffman, Corporal, # 1600; Kendrick Bailey # 1794; Stephen J. Berry, Corporal, # 1027; Joe B. Walker, Corporal, # 1321; John Piazza, Corporal, # 1353; Jeffrey P. Reichert, Corporal, # 31587; Kenneth O'berry, Detective, Corporal, # 1308; William B. Evartt, Corporal, # 1592; Robert Sheehan, Corporal, # 735; Edwin Robertson, Corporal, # 1233; Thomas R. Brown, Corporal, # 1064; Percel O. Alston, Corporal, # 1171; Ronald P. Ledonne, Sergeant, # 911; Clifford Holly, Captain, Individually and in His Official Capacity; Patrick Musselman, Corporal, # 1425; Roger Irvin, Corporal; Paul Evans, Sergeant, # 946; Howard Shook, Jr., Corporal, # 662; Daniel L. Husk, Captain, # 650; Ophus Robertson, Corporal, Retired; Unknown Officers, # 1-10, Defendants, 302 F.3d 188 (4th Cir. 2001)

These appeals arise from a jury verdict rendered against five law enforcement officers in the District of Maryland in October 2000. The verdict awarded compensatory and punitive damages to the plaintiffs, pursuant to the provisions of 42 U.S.C. § 1983 n1 and Article 24 of the Maryland Declaration of Rights. n2 The five officers have appealed the judgment of the district court, and the plaintiffs have cross-appealed certain pre-verdict rulings and the attorneys' fee award made to them. As explained below, we affirm the judgment as to two of the officers and the court's pre-verdict rulings. We vacate the judgment against the other three officers, however, and we vacate and remand the award of attorneys' fees.

On the evening of April 26, 1995, Corporal John Novabilski, a police officer in Prince George's County, Maryland, was murdered as he sat in his police cruiser. This event resulted in an extensive search and investigation by the County's Police Department (the "County Police"), during which they encountered the fourteen plaintiffs (collectively, the "Plaintiffs") in this proceeding. n3 The Plaintiffs subsequently filed suit in the state court of Prince George's County and, on July 19, 1996, their case was removed to the District of Maryland. After resolution of several procedural issues, the Plaintiffs, on April 29, 1998, filed their fifty-five count final amended complaint (the "Complaint"). They therein asserted various claims against several County Police officers, and against the County itself, pursuant to § 1983, Article 24 of the Maryland Declaration of Rights ("Article 24"), and Maryland tort law. They contended in substance that the County Police had assaulted and unlawfully detained them during the Novabilski investigation.

Following discovery, the defendants sought summary judgment on the Plaintiffs' claims and, on September 13, 1999, the court awarded summary judgment to them on the Maryland tort claims and on the Monell claims against Prince George's County. n4 The case thereafter proceeded to trial on claims of police misconduct during the Novabilski investigation, in contravention of the Plaintiffs' state and federal constitutional rights. The trial consumed nearly three weeks, from October 10 through October 27, 2000, and before the case was submitted to the jury, twenty of the twenty-seven defendants were dismissed. At the conclusion of its deliberations, the jury found three supervisory officers, Lieutenant F. Michael McQuillan, Sergeant George Swope, and Corporal Stephen Ricker (the "Supervisors"), liable to twelve of the Plaintiffs (the "Appellees"). The verdict against the Supervisors was based on the indirect liability concepts of "bystander" and "supervisory" liability, and the Appellees were awarded both compensatory and punitive damages under § 1983 and Article 24. The jury found two other officers, Corporals David Rosser and James Silvers (the "Corporals"), liable to Plaintiff Randall for a violation of Article 24. In post-trial proceedings, the district court, pursuant to 42 U.S.C. § 1988, awarded the Plaintiffs the sum of $ 195,000 for attorneys' fees and costs. n5

The Supervisors and the Corporals, plus Prince George's County (collectively, the "Appellants"), have appealed the adverse judgment, challenging both the liability of the Supervisors and the damage awards made to the Appellees. n6 The Appellants maintain that the evidence was insufficient to warrant a verdict against the Supervisors on any theory of indirect liability, and they contend that the damage awards are excessive.

The fourteen Plaintiffs have cross-appealed, contending that the evidence was sufficient to defeat summary judgment on their Monell claims, and also maintaining that the award of attorneys' fees was insufficient and erroneously calculated. n7 After first reviewing the factual underpinnings of these claims, we address the issues in turn.

In order to properly assess the issues on appeal, we must first understand the events that occurred in Prince George's County in the thirty-six hour period following the murder of Corporal Novabilski. In describing the evidentiary predicate for these events, we utilize four sub-parts: (1) The Parties; (2) the April 26-27, 1995 Search (the "First Search"); (3) the April 27-28, 1995 Detentions (the "Detentions"); and (4) the April 28, 1995 Search (the "Second Search"). n8

a.

The fourteen Plaintiffs are connected in varying ways to the residence located at 7211 East Forest Road in Landover, Maryland ("7211"). Between April 26 and April 28, 1995, the following thirteen persons were either living or present at 7211:

. Eloise Jones, the owner of 7211, lived there with her adult children: Edward Jones, Carlos Marshall, and Tamara Marshall;

. Tamara Marshall's two children, Carlton and Shanequia, lived at 7211, and Tamara's boyfriend, David Randall, was staying there;

. Eloise's brother, John Williams, and her first cousin, Jerry Vance, lived in the basement of 7211;

. Eloise's nephew, Dana Williams, and Dana's friend, Steve McAbee, slept at 7211; and

. Carlos Marshall's girlfriend, Yolanda Hamlet, and her baby, were also staying at 7211.With the exception of Carlton Marshall and Hamlet's baby, each of these persons is a plaintiff in this proceeding. These eleven plaintiffs are joined by three others who visited 7211 on April 27, 1995: Jerry Swint (a cousin of Eloise Jones), Jermaine Mayhew, and Jason Mobley (friends of Carlos Marshall and Edward Jones).

b.

The Appellants are five members of the County Police, plus the County itself. Three Appellants (Ricker, Swope, and McQuillan) are the County Police officers who supervised the Novabilski investigation. The primary responsibility for investigating and apprehending Novabilski's murderer rested with the Homicide Unit of the Criminal Investigations Division ("CID") of the County Police. The CID, a division of the County Police Bureau of Investigative Services, is responsible for major criminal investigations in the County. It is divided into four units: Homicide, Sexual Assault, Robbery, and Special Investigations. At the time of the murder, the Homicide Unit was commanded by Lieutenant McQuillan, and it was comprised of three squads. Each squad had a sergeant as its squad supervisor, and each squad also had five or six detectives. The Novabilski investigation was assigned to Corporal Ricker, a detective whose squad supervisor was Sergeant Swope. The three Supervisors (McQuillan, Swope, and Ricker) bore primary responsibility for the conduct of the investigation.

The other three Appellants are the Corporals and the County itself. Corporals Rosser and Silvers were members of the County Police who encountered nine of the plaintiffs during the First Search on April 26-27, 1995. The County is a party to these appeals due to its respondeat superior liability under Maryland law. See supra note 6.

After Corporal Novabilski was fatally shot, the murderer stole his service revolver and, according to witnesses, fled into the surrounding neighborhood. Several members of the County Police, including Corporal Rosser, promptly arrived at the liquor store parking lot where the murder occurred, and they quickly dispersed in search of the assassin. Approximately fifteen minutes after the 11:20 p.m. shooting, Corporal Henry Oldfield observed two men, Plaintiffs Edward Jones and Dana Williams, standing next to a burgundy Dodge Diplomat parked in front of 7211, which is located a short distance from the crime scene. Corporal Oldfield promptly conducted a stop and frisk procedure on the two men and radioed for back-up support.

Several officers responded to the request for assistance, including the Corporals (Rosser and Silvers). Upon arriving at the residence, the Corporals approached 7211 and spoke with Plaintiff Eloise Jones. Corporal Rosser then entered 7211 and encountered Jones's daughter, Plaintiff Tamara Marshall. He continued upstairs into a bathroom and discovered Plaintiff Randall in the bathtub. Rosser then gave Randall his boxer shorts and directed him outside for an interview. n9 Based on Randall's heavyset build and the fact that he did not appear to be out of breath, the Corporals did not consider him to be a perpetrator of the murder. Randall, along with, among others, Plaintiffs Edward Jones, Dana Williams, Vance, McAbee, and John Williams, were then lined up on their knees near a yard fence and questioned for about sixty minutes concerning the murder. Corporal Oldfield took photographs, obtained clothing samples, and recorded the physical features of the men at the fence. They were then released and advised to stay off the streets for the balance of that night.

a.

In its effort to identify and locate the culprit, the Homicide Unit enlisted and utilized officers from other CID units, and CID personnel conducted multiple investigative interviews in the early hours of April 27, 1995. Early on the morning of April 27, 1995, Darryl Hensley, a purported witness to the murder, was brought to the building that houses the CID offices (the "CID Station"). n10 Hensley, who was interviewed extensively, reviewed photographs and identified Jeffrey Gilbert, a nephew of Plaintiff Eloise Jones, as Corporal Novabilski's murderer. At approximately 5:30 p.m. on April 27, 1995, an arrest warrant was obtained for Gilbert, charging him with Novabilski's murder. At about that time, CID personnel discovered that the burgundy Dodge Diplomat that had been parked in front of 7211 the previous evening was registered to Gilbert. Search warrants were then obtained for both the Diplomat and the residence at 7211.

At approximately 9:00 p.m. on April 27, 1995, Lieutenant McQuillan conducted a briefing on the Novabilski investigation at the CID Station, and teams of officers were assigned to surveillance duty at 7211 and to locate the Diplomat. Over the course of the night, the surveillance officers stopped nine of the plaintiffs -- Randall, Swint, McAbee, Edward Jones, Dana Williams, Carlos Marshall, Mayhew, Mobley, and Hamlet -- in the vicinity of 7211.

b.

The stops made by the officers monitoring 7211 shared the common characteristics of what is known as a "high-risk felony stop." n11 In each instance, officers approached an individual or vehicle with their weapons drawn, contacted CID by radio, and advised the radio operator of the individual's identity. The nine plaintiffs stopped near 7211 were delivered to the CID Station through its back entrance, which is normally utilized only for persons in custody. Upon their arrival, they were taken to separate interview rooms, handcuffed to the metal loop protruding from the wall, and then interviewed. n12

Gilbert, for whom the arrest warrant had been issued on April 27, 1995, was located, apprehended, and delivered to the CID Station at approximately 2:30 a.m. on April 28, 1995. After the arrest, the authorities released Plaintiff Dana Williams; the other eight plaintiffs, however, remained at the CID Station for up to nine hours after Gilbert's apprehension. n13 The relevant experiences of these nine plaintiffs are summarized below.

(1) Plaintiff Randall

Shortly after 9:30 p.m. on April 27, 1995, the officers at 7211 stopped the burgundy Dodge Diplomat, which was being driven by Plaintiff Randall. Randall was transported to the CID Station, taken to an interview room, and handcuffed to a wall. At Sergeant Swope's direction, Detective Andrew Rositch interviewed Randall and reported the contents of the interview to Swope. Rositch did not release Randall because he understood that only the lead investigator, Corporal Ricker, or one of the other Supervisors, possessed the authority to release him. Officer Keith Harmon later questioned Randall again, but also did not release him.

Plaintiff Randall was moved to other interview rooms during the night and, after each move, was handcuffed to a wall. At about 5:00 a.m. on April 28, 1995, Randall was taken to the District III Station, registered as a prisoner, and locked in a cell. n14 He was released from the cell approximately an hour later, and, after retrieving his property, left the CID Station around 9:00 a.m. on April 28, 1995.

(2) Plaintiff Swint

Sometime before 10:00 p.m. on April 27, 1995, the surveillance officers stopped Plaintiff Swint, who was exiting 7211 on foot. They transported him to the CID Station, where either Swope or Ricker directed Corporal Edwin Robertson to interview him. Swint cooperated and signed a statement. However, he was not released because, according to Robertson, only the lead investigator had the authority to release him. Swint remained locked in an interview room until 9:00 a.m. on April 28, 1995, when he was heard banging on the door. He was then released from the CID Station.

(3) Plaintiff McAbee

Plaintiff McAbee was stopped by the surveillance officers shortly before 10:00 p.m. on April 27, 1995, while walking from 7211 to his mother's nearby home. He was transported to the CID Station and questioned about Gilbert. McAbee was handcuffed to a wall for six or seven hours and repeatedly sought to use the bathroom. Eventually, he was permitted to use the bathroom, but he was returned to the interview room and again handcuffed to the wall. He was later taken to the District III Station, registered as a prisoner, and placed in a cell. McAbee was released from the CID Station at approximately 11:00 a.m. on April 28, 1995.

(4) Plaintiffs Edward Jones, Dana Williams, Carlos Marshall, and Mayhew

At approximately 10:40 p.m. on April 27, 1995, the surveillance officers stopped a gold Toyota Camry departing 7211 carrying four men: Plaintiffs Edward Jones, Dana Williams, Carlos Marshall, and Mayhew. They were transported to the CID Station, taken to separate interview rooms, and handcuffed to walls. Edward Jones was questioned for several hours and advised that if he gave a statement, he would be permitted to leave. Upon providing a statement, however, he was not released. Two of the interviewing officers testified they could not release him until someone with more knowledge of the investigation had reviewed his statement for accuracy. At about 5:00 a.m. on April 28, 1995, Edward Jones was taken to the District III Station, registered as a prisoner, and placed in a cell. He was released from the CID Station at 9:45 a.m. on the morning of April 28.

Plaintiff Dana Williams was repeatedly interviewed on the night of April 27, 1995. Williams was released at approximately 2:30 a.m. on April 28, 1995. Plaintiffs Carlos Marshall and Mayhew were stripped of their personal items before being placed in separate interview rooms. They were handcuffed to walls throughout the interview process, and they were denied access to the bathroom despite repeated requests. Mayhew agreed to assist the police by paging Gilbert; however, after doing so, he was returned to the interview room and again handcuffed to the wall. Officer John Piazza also interviewed Mayhew and reported the contents of the interview to either Swope or Ricker. At approximately 5:00 a.m. on April 28, 1995, Marshall and Mayhew were taken to the District III Station, registered as prisoners, and placed in cells. They were released shortly before 6:00 a.m. on April 28, 1995.

(5) Plaintiffs Mobley and Hamlet

Between 10:45 and 11:15 p.m. on April 27, 1995, the surveillance officers at 7211 stopped a red Chevrolet occupied by Plaintiffs Mobley and Hamlet. They were transported to the CID Station and placed in separate interview rooms; Mobley was handcuffed to a wall. Either Sergeant Swope or another Homicide Unit sergeant directed an officer to interview Mobley, who was also interviewed by other officers during the night. Mobley initially refused to answer questions, asserting that he was under no obligation to do so. Officers then threatened him with incarceration if he refused to respond, and he relented. Hamlet was interviewed and then locked in an interview room. At approximately 5:00 a.m. on April 28, 1995, Mobley and Hamlet were taken to the District III Station, registered as prisoners, and locked in cells. They were released sometime on the morning of April 28, 1995.

At approximately 4:30 a.m. on April 28, 1995, the County Police executed the search warrant for 7211. The residence was then occupied by Plaintiffs Eloise Jones, Vance, John Williams, Tamara Marshall, and Shanequia Marshall, as well as two non-plaintiffs (Carlton Marshall and Plaintiff Hamlet's baby). After searching the premises of 7211, the officer-in-charge, Sergeant Howard Shook, had the occupants transported to the CID Station.

Plaintiff Tamara Marshall was thereafter locked in an interview room with her two children, and she was interviewed by several officers. She was advised that she would not be released until she signed a statement; however, upon signing a statement, she was not released. She and her two children were allowed to leave the CID Station sometime on the morning of April 28, 1995.

Plaintiff Vance was also locked in an interview room and handcuffed to a wall, and he was later interviewed by Corporal Robert Sheehan. At about 11:00 a.m. on April 28, 1995, Vance was informed of an outstanding warrant for his arrest due to a parole violation; he therefore remained in custody. n15

The trial in this case was conducted on the Plaintiffs' claims of police misconduct during the First Search, the Detentions, and the Second Search. Prior to trial the Plaintiffs voluntarily dismissed their claims against the law officers who had detained, transported, and interviewed them. The Plaintiffs instead chose to pursue only their claims against the law officers who conducted the First Search, the primary investigators, certain officers who had incarcerated several plaintiffs in the District III Station cells, and supervisory officials of CID. During trial, the court directed verdicts in favor of most of the defendants. As such, the jury considered in substance the following questions:

1) The First Search: Whether Corporals Oldfield, Rosser, and Silvers violated the constitutional rights of Plaintiffs Edward Jones, Dana Williams, Randall, McAbee, Vance, and John Williams;

2) The Detentions: Whether the Supervisors violated the constitutional rights of Plaintiffs Randall, Edward Jones, Dana Williams, Mayhew, Carlos Marshall, Hamlet, Mobley, McAbee, and Swint; and

3) The Second Search: Whether the Supervisors and Sergeant Shook violated the constitutional rights of Plaintiffs Eloise Jones, Tamara Marshall, Shanequia Marshall, Vance, and John Williams.

In connection with its deliberations, the jury answered special interrogatories addressing the various issues and theories in the case. In summary, the verdict made the following findings:

1) The First Search: The jury found that the Corporals had seized Plaintiff Randall in violation of his federal and state constitutional rights. The jury also found, however, that the Corporals were entitled to qualified immunity with respect to the federal constitutional violation. n16 The jury awarded Randall $ 10,000 in compensatory damages against Rosser, Silvers, and the County, jointly and severally.

2) The Detentions and the Second Search: The jury found that the Supervisors were liable to all Plaintiffs except Eloise Jones and John Williams. Although the jury found in favor of the Supervisors on the theory of direct liability, it found that Swope and Ricker were liable on a theory of bystander liability and that McQuillan was liable on a theory of supervisory liability. n17

3) The Damages: The jury awarded the twelve recovering plaintiffs between $ 5,000 and $ 45,000 each in compensatory damages, jointly and severally against the Supervisors and the County. n18 It also awarded punitive damages against the Supervisors, and in favor of the nine plaintiffs involved in the Detentions. Each of the nine plaintiffs received punitive damages in the sum of $ 10,500, with Ricker being assessed $ 2,500 per plaintiff, Swope $ 3,500 per plaintiff, and McQuillan $ 4,500 per plaintiff.

Both the Appellants and the Plaintiffs filed post-trial motions. In their motions, the Appellants challenged their liability and the various damage awards. The Plaintiffs, on the other hand, contested the verdict in favor of the Corporals with respect to five plaintiffs, and they challenged the directed verdict awarded to Corporals William Evartt and Joseph Hoffman. n19 By its Opinion of February 6, 2001, the district court denied the post-trial motions, upheld the verdict in all respects, and awarded the Plaintiffs their attorneys' fees and costs. Randall v. Prince George's County, Opinion, Civ. No. AW-96-2296 (D. Md. Feb. 6, 2001) (the "Opinion").

Both the Appellants and the Plaintiffs have appealed the judgment of the district court. In connection with the direct appeal, we are presented with five issues:

First, Sergeant Swope and Corporal Ricker challenge the court's imposition of liability on a theory of bystander liability. They assert in the alternative that the district court's jury instruction on bystander liability was erroneous;

Second, Lieutenant McQuillan contends that the court improperly imposed § 1983 liability on a theory of supervisory liability. McQuillan maintains in the alternative that the jury instruction on supervisory liability was erroneous;

Third, the Appellants maintain that, if they are liable for violating the Appellees' constitutional rights, an award of nominal damages is the only appropriate relief;

Fourth, the Supervisors maintain that the evidence is insufficient to support an award of punitive damages; and

Fifth, the Appellants contend that the damage awards are excessive.

The Plaintiffs raise three issues by way of their cross-appeal. n20 First, they challenge the summary judgment awarded to Prince George's County on their Monell claims; second, they assert that the court erred in granting the directed verdict to Evartt and Hoffman; and third, they maintain that the court erroneously calculated the attorneys' fee award of $ 195,000.

We possess jurisdiction over these appeals pursuant to 28 U.S.C. § 1291.

We review de novo the denial of a directed verdict, or the denial of judgment notwithstanding the verdict. Price v. City of Charlotte, North Carolina, 93 F.3d 1241, 1245 (4th Cir. 1996). We will not, however, disturb a jury verdict "unless, without weighing the evidence or assessing witness credibility, we conclude that reasonable people could have returned a verdict" only for the moving party. Cooper v. Dyke, 814 F.2d 941, 944 (4th Cir. 1987). In reviewing a jury verdict, we view the evidence, and all reasonable inferences therefrom, in the light most favorable to the prevailing party. Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 255, 91 L. Ed. 2d 202, 106 S. Ct. 2505 (1986).

We review de novo an award of summary judgment. Shaw v. Stroud, 13 F.3d 791, 798 (4th Cir. 1994). In so doing, we stand in the same position as the district court, and we will uphold an award of summary judgment "if the pleadings, depositions, answers to interrogatories, and admissions on file, together with the affidavits, if any, show that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law." Fed. R. Civ. P. 56(c).

In reviewing an award of compensatory or punitive damages, we affirm the award unless it is against the clear weight of the evidence, based upon evidence that is false, or would result in a miscarriage of justice. Cline v. Wal-Mart Stores, Inc., 144 F.3d 294, 305 (4th Cir. 1998). We review an award of § 1988 attorneys' fees for abuse of discretion. Brodziak v. Runyon, 145 F.3d 194, 196 (4th Cir. 1998).

The issues before us fall into four basic categories: two relating to the contentions of the Appellants and two others relating to the contentions of the Plaintiffs. First, the Supervisors challenge the jury verdict that they are liable for the deprivations suffered by the Appellees on April 27-28, 1995. In that regard, they maintain that the evidence is insufficient to warrant the verdict on any theory of indirect liability. Second, the Appellants challenge the damage awards against them, contending that they are excessive.

The Plaintiffs, on the other hand, maintain that the award of summary judgment to Prince George's County on the Monell claims was improper. They contend that they produced sufficient evidence of a custom and usage by the County Police, in detaining witnesses against their will and without probable cause, to create a genuine issue of material fact. Second, the Plaintiffs assert that the award of attorneys' fees was erroneously calculated, contending that the court failed to account for work performed on claims that were unsuccessful. We address each of these issues in turn.

The Supervisors have appealed the findings of liability against them under § 1983 and Article 24. n21 Two of the Supervisors, Sergeant Swope and Corporal Ricker, maintain that the evidence is insufficient to sustain the verdict against them on the theory of bystander liability. Similarly, Lieutenant McQuillan maintains that there was insufficient evidence to sustain the verdict against him on the theory of supervisory liability. As explained below, these contentions have merit.

Under § 1983, a state actor may be liable if he "subjects, or causes to be subjected" an individual "to the deprivation of any rights, privileges, or immunities secured by the Constitution." As a general matter, a law officer may incur § 1983 liability only through affirmative misconduct. See generally Parratt v. Taylor, 451 U.S. 527, 535-36, 68 L. Ed. 2d 420, 101 S. Ct. 1908 (1981), overruled on other grounds by Daniels v. Williams, 474 U.S. 327, 88 L. Ed. 2d 662, 106 S. Ct. 662 (1986). In this case, however, the jury found that the Supervisors had not engaged in any affirmative conduct that deprived the Appellees of their federally protected rights. It instead based its verdict against them on two theories of indirect liability: "bystander liability" as to Swope and Ricker, and "supervisory liability" as to McQuillan. n22

Although personal liability premised on an omission is a disfavored concept, it is well-established that an omission to act, when coupled with a duty to act, may provide a basis for liability. The concepts of bystander and supervisory liability are each premised on omissions, but there are significant differences between them. The concept of bystander liability is premised on a law officer's duty to uphold the law and protect the public from illegal acts, regardless of who commits them. See infra Part IV.A.3.a. Therefore, if a bystanding officer (1) is confronted with a fellow officer's illegal act, (2) possesses the power to prevent it, and (3) chooses not to act, he may be deemed an accomplice and treated accordingly. See O'Neill v. Krzeminski, 839 F.2d 9, 11-12 (2d Cir. 1988) (observing that officer who stands by and does not seek to assist victim could be "tacit collaborator").

On the other hand, the theory of supervisory liability arises from the obligation of a supervisory law officer to insure that his subordinates act within the law. See infra Part IV.A.4.a. Although such a supervisor may not prevent all illegal acts by his subordinates, he is obligated, when on notice of a subordinate's tendency to act outside the law, to take steps to prevent such activity. If a supervisory law officer is deliberately indifferent to that responsibility, he then bears some culpability for illegal conduct by his subordinates, and he may be held vicariously liable for their illegal acts. Shaw v. Stroud, 13 F.3d 791, 798 (4th Cir. 1994).

Thus, although the separate concepts of bystander and supervisory liability arise from a failure to act in the presence of a duty, they are based on differing duties and obligations, and our analysis of them is separate and distinct. With this overview in mind, we now turn to the Supervisors' specific challenges to the verdict.

Sergeant Swope and Corporal Ricker maintain that the court erred in submitting the theory of bystander liability to the jury, contending that the evidence against them is insufficient. In addressing this contention, we recognize that our Court has not definitively assessed the circumstances under which bystander liability might attach to a law officer, although we have indicated that such circumstances may exist. See Jackson v. Pantazes, 810 F.2d 426, 430 (4th Cir. 1987) (observing that liability might be found when officer failed to intervene to stop state actor from performing unconstitutional search). As such, we must first address whether, and under what circumstances, officers may be subjected to bystander liability under § 1983.

a.

Several of our sister circuits have adopted a framework for assessing the applicability of bystander liability for law officers. See Skrtich v. Thornton, 280 F.3d 1295, 1301 (11th Cir. 2002); Mick v. Brewer, 76 F.3d 1127, 1136 (10th Cir. 1996); Yang v. Hardin, 37 F.3d 282, 285 (7th Cir. 1994); Anderson v. Branen, 17 F.3d 552, 557 (2d Cir. 1994); Bruner v. Dunaway, 684 F.2d 422, 425-26 (6th Cir. 1982); Putman v. Gerloff, 639 F.2d 415, 423 (8th Cir. 1981); Byrd v. Brishke, 466 F.2d 6, 11 (7th Cir. 1972). As a general proposition, these courts have concluded that an officer possesses "an affirmative duty to intervene to protect the constitutional rights of citizens from infringement by other law enforcement officers." Anderson, 17 F.3d at 557. According to the Second Circuit, such a duty attaches when an officer observes or has reason to know that a "constitutional violation [is being] committed" by other officers and possesses "a realistic opportunity to intervene to prevent the harm from occurring." Id.; see also Yang, 37 F.3d at 285.

This standard recognizes that, in certain limited situations, bystanding officers are obliged to act. n23 As the Seventh Circuit cogently observed in Byrd v. Brishke, "it is clear that one who is given the badge of authority of a police officer may not ignore the duty imposed by his office and fail to stop other officers who summarily punish a third person in his presence or otherwise within his knowledge." 466 F.2d at 11. Any rule to the contrary would permit officers to ignore their duty to enforce the law. Therefore, an officer may be liable under § 1983, on a theory of bystander liability, if he: (1) knows that a fellow officer is violating an individual's constitutional rights n24; (2) has a reasonable opportunity to prevent the harm; and (3) chooses not to act.

b.

With this test for bystander liability in mind, we turn to the contention of Swope and Ricker that the evidence does not support the verdict against them. Applying the three-part test enunciated here, we must assess whether the evidence is sufficient to show that either Swope or Ricker knew the Appellees were being unlawfully detained on April 27-28, 1995, and that, having such knowledge, either of them failed to exercise a realistic opportunity to intervene and end the unlawful detentions.

It is clear that Swope and Ricker, if they were aware that the Appellees were being detained unlawfully, had an opportunity to end the detentions, and they did not do so. Thus, the relevant question is whether the evidence warrants a finding that Swope and Ricker knew the Appellees were being unlawfully detained. In assessing that issue, the knowledge of Swope and Ricker must be evaluated separately with respect to each of the Appellees. In order for the verdict to be sustained, the evidence must show that they knew three things: (1) that a particular Appellee was present at the CID Station on April 27-28, 1995; (2) that there was an absence of probable cause to detain that Appellee; and (3) that such Appellee was being held against his or her will. Viewed in the light most favorable to the Appellees, the evidence on these points is as follows:

. Swope and Ricker knew that there was probable cause to arrest only Jeffrey Gilbert;

. Various Appellees had been brought to the CID for inter views;

. The routine procedure in a major investigation was that the lead investigator or his superior (i.e., Swope or Ricker) reviewed witness statements at some point;

. The routine procedure was that witnesses were not released until the lead investigator or his supervisor were satisfied that the interviews were complete and gave approval;

. Some of the Appellees screamed, banged on doors, and yelled about being detained in interview rooms;

. The Appellees were moved about the CID Station in handcuffs during the night;

. Swope and Ricker were in the central area of the CID

Station for most the night of April 27-28, 1995, and they might have heard the Appellees; and

. Swope and Ricker might have seen the Appellees being transported in handcuffs.This evidence, however, fails to demonstrate a bystander liability case against Swope or Ricker. Significantly, the CID was conducting multiple investigations on the night of April 27-28, 1995, and there were many interviewees present at the CID Station that evening who were entirely unconnected to the Novabilski investigation. Although the evidence demonstrates that Swope and Ricker knew that (1) some of the Appellees were present at the CID Station, and that (2) individuals were being detained there against their will, it fails to show that Swope and Ricker also knew that these two groups (i.e., the Appellees and the persons being involuntarily detained) were one and the same. And with the substantial number of persons present at the CID Station that evening, such a connection cannot be satisfied through mere inference.

In the final analysis, the viability of the bystander liability verdict turns on what Swope and Ricker knew about each of the Appellees. When examined in that light, there is no evidence that either of them knew that Plaintiffs Edward Jones, Dana Williams, Carlos Marshall, Hamlet, McAbee, Tamara Marshall, and Vance were present at the CID Station, or that they, collectively or individually, were being detained against their will. Although either Swope or Ricker knew that Plaintiffs Mayhew, Mobley, and Swint were present at the CID Station, and also knew that there was no probable cause for any of them to be detained, there is no evidence that either Swope or Ricker knew that any of them was being held involuntarily. Finally, there is no evidence that either Swope or Ricker knew that Plaintiff Shanequia Marshall was present at the CID Station that evening.

The evidence as to Plaintiff Randall presents a more difficult question. Officer Rositch testified at trial that he gave Randall's statement to Swope and that Swope reviewed its contents. Coupled with the evidence summarized above, there is sufficient evidence for a jury to conclude that Swope knew that there was no probable cause to hold Randall and that Randall had not been released. There is no evidence, however, that Swope knew that Randall was being detained against his will. As far as Swope knew, Randall could have been at the CID Station voluntarily. Thus, there is no basis on which the jury could reasonably conclude that Swope knew Randall was involuntarily present in the CID Station. Moreover, there is no evidence that Ricker knew anything about Randall's presence at the CID Station. As such, the evidence is insufficient to support the bystander liability verdict against Swope and Ricker as to any of the Appellees. n25

Lieutenant McQuillan also challenges the verdict against him, which is based on supervisory liability. McQuillan maintains that, as a matter of law, supervisory liability cannot attach in the absence of prior constitutional abuses by subordinates. He contends that the evidence fails to show any such abuses.

a.

As we enunciated in Shaw v. Stroud, 13 F.3d 791 (4th Cir. 1994), supervisory liability may attach under § 1983 if a plaintiff can establish three elements. These are: (1) "that the supervisor had actual or constructive knowledge that his subordinate was engaged in conduct that posed â