ERICK A. RALDA DELEON v. GRACO INC

NOT FOR PUBLICATION WITHOUT THE

APPROVAL OF THE APPELLATE DIVISION

 

SUPERIOR COURT OF NEW JERSEY

APPELLATE DIVISION

DOCKET NO. A-1341-09T2

ERICK A. RALDA DELEON,

Plaintiff-Appellant,

v.

GRACO INC.,

Defendant-Respondent.

____________________________________

Argued March 2, 2011 Decided July 7, 2011

 

Before Judges Cuff, Sapp-Peterson and Simonelli.

 

On appeal from the Superior Court of New Jersey, Law Division, Essex County, Docket L-6321-06.

 

Mark J. Cintron argued the cause for appellant (Law Offices of Lawrence M. Simon, attorneys; Mr. Simon and Mr. Cintron, on the brief).

 

Scott M. Rusert (Flynn, Gaskins & Bennett, L.L.P.) of the Minnesota Bar, admitted pro hac vice, argued the cause for respondent (Wade Clark Mulcahy, and Mr. Rusert, attorneys; Denise Fontana Ricci and Mr. Rusert, on the brief).

PER CURIAM

In this products liability matter, plaintiff Erick Ralda DeLeon appeals from the denial of his motion for reconsideration of the grant of summary judgment to defendant Graco, Inc. (Graco) and dismissal of plaintiff's complaint with prejudice. The motion judge concluded that plaintiff's liability expert rendered a net opinion on the cause of the injury plaintiff sustained while cleaning a high-pressure paint spray gun, which Graco manufactured. We conclude that plaintiff's expert rendered a net opinion as to some, but not all of, the defects of the spray gun that the expert concluded caused plaintiff's injury. We, thus, affirm in part, and reverse in part.

Plaintiff was employed as a painter by Garden State's Dun-Rite Painting (Dun-Rite). On August 31, 2004, plaintiff was injured by a spray gun when he attempted to clean it.

Plaintiff's liability expert, Paul Tutton, described the spray gun as follows. The spray gun has a handle grip with a four-finger trigger and removable nozzle assembly that has a cylindrical or plug valve referred to as the tip, through which the paint flows. In order for the spray gun to function, it had to be pressurized by a compressor, which was attached to the spray gun through hoses. According to Dun-Rite's policy, the pressure setting on the compressor had to be turned down before cleaning the spray gun.

The trigger is one feature of the spray gun that allows pressurized paint to flow through the spray gun. When the trigger is squeezed, the valve within the spray gun opens, allowing pressurized paint to pass through to the nozzle tip. When the trigger is not squeezed, it remains in a forward position. In this forward position, the valve is closed, and paint will not pass through to the nozzle. Thus, to open the valve to allow paint to pass through the spray gun, the trigger would have to be either pulled back or squeezed.

The trigger has a manual safety lock near the hinge of the trigger, which can lock the trigger in both the open-valve and closed-valve positions. To achieve the locked-open position, the user would squeeze the trigger, and the safety would rotate and manually engage. In the locked-open position, a slight squeeze of the trigger would allow a spring to release and disengage the safety. To achieve the locked-closed position, the user would have to manually push forward the trigger to allow the safety to be manually rotated into a locking position. There is no spring action associated with the locked-closed position.

The tip of the spray gun can be rotated to change the orientation and pattern of the nozzle. With the nozzle either forward or toward the handle, the paint would flow through the spray gun. Only rotating the nozzle completely to the side would block the flow of paint.

The rotating tip is inserted into a hole in the guard assembly. There are two stops to prevent over-insertion and rotation beyond an approximately 180-degree arc. Other than these two stops, the tip was only held in place by friction. Once the tip was inserted, only friction prevented rotation of the nozzle and tip from sliding out. The position of the arrow on the tip handle indicated the direction of the nozzle, but there was nothing to indicate whether the tip was fully inserted into the hole in the guard assembly. The spray gun also has a "retaining" nut that provides compression on the tip, making it stiffer and more difficult to move or remove when the nut is tightened.

Plaintiff testified at his deposition that after he finished spraying, his supervisor instructed him to clean the spray gun and to take out and replace the tip. The supervisor advised plaintiff that the spray gun was "ready" for cleaning. Plaintiff believed that the pressure had been turned down and did not check it because the compressor was off. However, by the time plaintiff picked up the spray gun, a co-employee had activated the compressor. Plaintiff then loosened the retaining nut "a little bit" and paint shot out from the front of the spray gun and the side where the tip was, injecting paint into the palm of his right hand. The tip apparently blew off and was never recovered.

Tutton stated in his report1 that in order for spray to discharge from the spray gun, three conditions had to be in place: (1) the spray gun had to be pressurized; (2) the trigger had to be squeezed; and (3) the nozzle had to be open. Once the spray gun was pressurized, there are two features that would permit the paint to flow through it. The first feature is the trigger lock, mentioned above, which could be manually locked in an open position. Tutton concluded that the manual trigger lock was defective because "the lock could be easily left disengaged allowing for accidental discharge of the high pressure paint."

The second feature is the tip, which had to be in the proper position in order for paint to pass through the nozzle. Tutton concluded the tip was defective because "there was no positive means to prevent rotation of the tip or limit tip insertion or withdrawal, [making it] foreseeable that [the tip] could be left in a position that would allow flow, either forward or backward." Also, there was "nothing to prevent inadvertent rotation of the arrow-shaped tip handle. With the tip positioned to block flow, it was a simple matter to knock the arrow handle to a position allowing flow or to be knocked to a partially disengaged position."

Tutton concluded within a reasonable degree of engineering certainty that the spray gun "incorporated the hazard of skin injection from the high pressure nozzle spray" and the "high pressure dispensing system was . . . necessary to the function of the paint spray." He also concluded that the spray gun's design was "inherently unsafe and dangerous" and, therefore, "defective" because Graco failed to adequately guard against a skin injection hazard by not: (1) providing a self-activating trigger lock, which would have forced the user to take a conscious step in order to operate the spray gun; (2) providing a positive and secure means of assuring the position of the tip in shutting off flow; (3) guarding against inadvertent mis-positioning of the tip; and (4) providing a secure method of engaging the retaining nut and stabilizing the position of the tip. He further concluded that "[t]hese design defects, independently or in combination, were the cause of [plaintiff's] injuries."

At Tutton's deposition, he acknowledged that plaintiff testified that he did not touch the trigger. Accordingly, Tutton supplemented his opinion, concluding that the feature of a manual trigger lock in an open position was a defect, and Graco prohibited use of such a lock after 2005. He explained that because plaintiff testified he did not touch the trigger and spray came out of the front and side of the tip and also "blew out" the tip, the trigger was in a manually locked-open position when plaintiff attempted to clean it, which enabled the gun to be pressurized without operator interaction. Consequently, when plaintiff loosened the tip in order to clean the spray gun, the pressure caused the tip to effectively blow apart, causing plaintiff's injury.

Tutton also concluded that the tip was defective because a user could easily re-position the tip from closed to open, could use it as a shut-off valve when it was not designed for that purpose, and could manipulate the retaining nut on the tip. Thus, if the spray gun were pressurized and the trigger were locked open, the tip would be the only mechanism preventing discharge. Because Graco did not design the tip to prevent discharge as a last resort, a user might inadvertently manipulate the tip from an "off" position or loosen the retaining nut, causing the paint to discharge. Tutton explained that

the loosening of the nut really frees up the tip to be manipulated in several directions and not the least of which is axial to the tip, which would allow it to come out all together and allow flow out [of] the side. [Plaintiff's] deposition testimony indicated that flow was coming out [of] the end and flow was coming out [of] the side and the tip was never recovered. So, what it suggests very strongly to me is that once this nut was loosened to provide the ability to clean it, [the tip] effectively blew apart.

 

Tutton also explained that the tip could be inadvertently nudged open because it did not have anything securing it in place, and inadvertent repositioning of the tip and instability would result if the retaining nut were not tight enough. Thus, either the user could accidentally nudge the tip open or fail to tightly screw the retaining nut, which if loose might cause the tip to fail.

Despite these opinions, Tutton could not opine within a reasonable degree of probability that each alleged defect in the tip independently caused plaintiff's injury. He agreed that it was "possible" that a defective tip caused plaintiff's injuries, which factor "certainly would have been one of a number of things that could have produced the injury to [plaintiff]."

Tutton also reiterated that the four original defects he identified in his report were the cause of the accident to a reasonable degree of engineering certainty. With respect to the trigger, it was defective because it lacked a self-activating trigger lock to prevent a user from inadvertently engaging the trigger. He explained that although plaintiff did not touch the trigger, his "opinion [about the trigger] is focused on the actual device," and the trigger "was a feature that did allow for inadvertent spray of the gun." However, he could not specifically say whether the absence of a self-activating trigger lock was a cause of plaintiff's injury. Nevertheless, he concluded that

these design defects, independently or in combination, were the cause of [plaintiff's] injuries. So, I don't know what happened specifically on the date of the incident. The condition, the equipment was such that it permitted any of the above things to happen . . . . So . . . the general condition of the design of the gun either together or in part or any combination thereof, were the cause of the accident.

 

Graco filed a motion for summary judgment and submitted a statement of material facts, Tutton's two reports, and selected portions of Tutton's deposition testimony, among other things. Graco argued that plaintiff could not prove causation because Tutton rendered a net opinion that did not establish within a reasonable degree of certainty which defect actually caused plaintiff's injury. Graco also argued that the absence of a self-activating trigger lock could not have reasonably caused plaintiff's injury because plaintiff did not touch the trigger.

Plaintiff's counsel failed to file a counter-statement of material facts or submit Tutton's complete deposition transcript. Counsel also conceded at oral argument that Tutton could not opine which defect caused plaintiff's injury. Counsel argued, however, that Tutton did not render a net opinion; rather, he explained that plaintiff's injury would not have occurred but for the lack of a safety feature, such as a self-activating trigger lock and a tip that snapped into place and did not come off, thus, preventing the gun from inadvertently discharging paint. Counsel also requested a Rule 104 hearing.

The motion judge found that Tutton's report and the portions of his deposition testimony Graco submitted did not support plaintiff's arguments. The judge observed that Tutton did not opine that any of the defects independently caused plaintiff's injury and failed to explain how the defects collectively caused the injury. Further, rather than assume a set of circumstances and testify within a reasonable degree of certainty that the injury under any one circumstance could not have occurred but for the defects, Tutton limited his opinion to mere possibility. Thus, the judge concluded that Tutton's opinion amounted to assertions of enhanced risk, but not of causation, and constituted a net opinion. The judge also denied plaintiff's request for a Rule 104 hearing.

The judge invited plaintiff to file a motion for reconsideration if plaintiff submitted a certification from Tutton "explaining, based on what he said in his report, why he has the opinion that the design defects in combination were the cause of [plaintiff's] injuries." Plaintiff thereafter filed a motion for reconsideration supported by Tutton's certification, and Tutton's report and complete deposition transcript, and a response to Graco's statement of material facts.

In his certification, Tutton identified defects that independently or in combination made the spray gun inherently unsafe and dangerous. First, the spray gun lacked a self-activating trigger lock, which would prevent an inadvertent depression of the trigger. Second, the spray gun lacked a positive and secure means of assuring that the tip was in a position which shut off paint flow. Tutton explained that

[t]he tip position is totally dependent on how tight the nut is. For example, once the nut is loosened, even slightly, everything beyond it becomes free to move in multiple directions throughout the device. Thus, if the trigger of the [spray gun] was in the "on" position, once you manipulate the nut, everything beyond the nut becomes very loose. So, there is an incredible variety of stability of all of these parts depending on how tight the nut is.

 

Third, the spray gun lacked a definitive and secure means of guarding against inadvertent mis-positioning of the tip. Tutton explained that

[i]n this model, a 90-degree position of the tip is required to shut off the pressure. There is nothing to prevent the tip from being nudged and put back into a flow position. For example, there is no stop provided on the [spray gun] that would prevent the tip from moving from the shut off position.

 

Fourth, the spray gun lacked a secure method of engaging the retaining nut and stabilizing the position of the tip. Tutton explained that

once the nut is slightly loose, the position of the tip is very non-specific. Anything other than the desired position becomes a potential hazard. As a result, the whole design of the tip assembly is such that it is very dependent on the tightness of the nut, which is very subjective. Anything other than the desired position becomes a potential hazard.

 

Finally, the spray gun had a manual lock-open trigger device, which permitted the tip to be pressurized without the user's knowledge or without the user actively squeezing the trigger. Tutton concluded that "[t]he engagement of this lock-open device is consistent with [plaintiff's] testimony that he did not depress the trigger, yet the tip was pressurized." Tutton also concluded within a reasonable degree of engineering certainty that the spray gun's design was inherently unsafe and dangerous, and the defects, independently or in combination, caused plaintiff's injuries.

The judge denied plaintiff's motion for reconsideration essentially because plaintiff failed to provide the transcript of the motion for summary judgment. The judge stated,

I cannot tell on this record whether I wholly failed to appreciate the significan[ce] o[f] probative competent evidence. I think I did, and I may have gotten it wrong. But it doesn't mean that . . . I . . . see the way it's presented to me now is really that I start from scratch. . . . So I really have to have a complete record if I would ever consider this on reconsideration . . . .

 

This appeal followed.

On appeal, plaintiff argues, in part, that the judge erred in granting summary judgment and denying reconsideration, because Tutton did not render a net opinion. Plaintiff also argues that the judge improperly denied his request for a Rule 104 hearing, and we should remand this matter to a different judge.

Our review of a ruling on summary judgment is de novo, applying the same legal standard as the trial court. Coyne v. N.J. Dep't of Transp., 182 N.J.481, 491 (2005); Chance v. McCann, 405 N.J. Super. 547, 563 (App. Div. 2009). Thus, we consider, as the trial judge did, "'whether the evidence presents a sufficient disagreement to require submission to a jury or whether it is so one-sided that one party must prevail as a matter of law.'" Liberty Surplus Ins. Corp. v. Nowell Amoroso, P.A., 189 N.J. 436, 445-46 (2007) (quoting Brill v. Guardian Life Ins. Co. of Am., 142 N.J. 520, 536 (1995)). Summary judgment must be granted "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 challenged and that the moving party is entitled to a judgment or order as a matter of law." R. 4:46-2(c). If there is no genuine issue of material fact, we must then "decide whether the trial court correctly interpreted the law." Massachi v. AHL Servs., Inc., 396 N.J. Super. 486, 494 (App. Div. 2007), certif. denied, 195 N.J. 419 (2008). We review issues of law de novo and accord no deference to the trial judge's conclusions on issues of law. Zabilowicz v. Kelsey, 200 N.J. 507, 512-13 (2009).

As for reconsideration motions, we have determined,

Reconsideration itself is a matter within the sound discretion of the [c]ourt, to be exercised in the interest of justice[.] It is not appropriate merely because a litigant is dissatisfied with a decision of the court or wishes to reargue a motion, but should be utilized only for those cases which fall into that narrow corridor in which either 1) the [c]ourt has expressed its decision based upon a palpably incorrect or irrational basis, or 2) it is obvious that the [c]ourt either did not consider, or failed to appreciate the significance of probative, competent evidence.

 

[Palombi v. Palombi, 414 N.J. Super. 274, 288 (App. Div. 2010) (citations omitted) (internal quotation marks omitted).]

 

Accordingly, we will not disturb a trial judge's denial of a motion for reconsideration absent an abuse of discretion. Cummings v. Bahr, 295 N.J. Super. 374, 389 (App. Div. 1996).

Applying these standards, we conclude that the judge mistakenly denied reconsideration. Having invited the motion for reconsideration, the judge should have considered Tutton's certification, report, and entire deposition transcript to determine whether summary judgment was properly granted.

That said, we focus on whether the judge properly denied summary judgment because Tutton rendered a net opinion. Under the "net opinion" rule, "an expert's bare conclusions, unsupported by factual evidence [or other data], [are] inadmissible." Buckelew v. Grossbard, 87 N.J. 512, 524 (1981). The rule is frequently invoked in cases in which an expert fails to explain the "why and wherefore" of an opinion on causation. See ibid.

To survive summary judgment in a products liability case, the plaintiff must show that a product had a defect that proximately caused his or her injury. See Michalko v. Cooke Color & Chem. Corp., 91 N.J. 386, 394 (1982). The plaintiff must establish that a defective product was a substantial factor in bringing about an injury, but proof must be shown to a reasonable degree of probability. Grassis v. Johns-Manville Corp., 248 N.J. Super. 446, 457 (App. Div. 1991). An expert's opinion that contains unsupported speculation is insufficient to satisfy a plaintiff's initial burden. Vuocolo v. Diamond Shamrock Chems. Co., 240 N.J. Super. 289, 300 (App. Div.), certif. denied, 122 N.J. 333 (1990). "However, if an expert provides the whys and wherefores rather than bare conclusions it is not considered a net opinion." Beadling v. William Bowman Assocs., 355 N.J. Super. 70, 87 (App. Div. 2002).

An expert's opinion must be supported by factual evidence, not speculation. See Froom v. Perel, 377 N.J. Super. 298, 317 (App. Div.), certif. denied, 185 N.J. 267 (2005). The distinction between speculation and probability is relevant here. In Malin v. Union Carbide Corp., 219 N.J. Super. 428, 439 (App. Div.), certif. denied, 107 N.J. 638 (1987), we held that the plaintiff's expert rendered a net opinion because the expert's testimony about causation "was specifically couched in terms of possibility, rather than probability," therefore, "inferences drawn by the jury based on that opinion were mere speculation." While a party is not required to provide proof of certainty, "the evidence must be such as to justify an inference of probability" rather than possibility." Callahan v. Nat'l Lead Co., 4 N.J. 150, 155 (1950).

Tutton limited the scope of his opinion to the "dangerous configuration" of the spray gun. Resolving this matter, therefore, hinges on whether Tutton expressed mere possibilities or articulated facts sufficient to justify an inference of probability. To determine this, we shall discuss the defects Tutton identified as causing plaintiff's injury: the manual trigger lock and lack of a self-activating trigger lock, the tip, and retaining nut.

A. The Manual Trigger Lock

An expert must link the need for a new product design to the risk identified by the facts of the case and must also substantiate the risk involved with factual evidence. Koruba v. Am. Honda Motor Co., 396 N.J. Super. 517, 526-27 (App. Div. 2007), certif. denied, 194 N.J. 272 (2008). Tutton explained that because plaintiff did not touch the trigger, a prior user must have manually locked the trigger. If the trigger was locked open and the compressor was on, the spray gun would have been pressurized at the time plaintiff loosened the tip. Thus, once the tip was loosened, it could not withstand the pressure and effectively blew apart, causing plaintiff's injury. We are satisfied that Tutton's opinion -- that the manual trigger lock was a defect -- was supported by factual evidence.

However, to be admissible, the opinion must also be couched in terms of reasonable certainty or probability. Vuocolo, supra, 240 N.J. Super. at 300. To determine whether Tutton adequately explained causation in terms of certainty or probability requires a closer examination of the substance of his opinion and not solely the terminology he used. When asked to opine to a reasonable degree of certainty as to whether the absence of a self-activating trigger lock caused plaintiff's injury, Tutton seemed reticent to do so. He also stated that his "opinion is focused on the actual device." He limited his opinion to nothing more than "that the design of this gun enabled an operator to be in a dangerous position with a dangerous configuration of the gun." He attributed causation to the "general condition of the design of the gun," and admitted that it is "possible" that any one of the defects was a cause of plaintiff's injuries. He also did not state that the defect was a substantial factor in bringing about the injuries.

In Johnesee v. Stop & Shop Cos., 174 N.J. Super. 426, 430 (App. Div. 1980), the trial court excluded defendant's expert's opinion because it did not mention "medical probability," the opinion referring only to "possibilities." Although we agreed that an expert's opinion must ordinarily be couched in terms of certainty or probability, we determined that regardless of the terminology used by the expert, the expert's report could be interpreted in terms of medical probabilities. Id. at 431. The expert had labeled his opinions with the word "possibilities," but upon our closer examination of his conclusion that "[h]epatitis as a result of the contaminated food which did not produce hepatitis in the wife," we determined that the expert "clearly expressed the opinion that it was not reasonably probable that the [food] caused the hepatitis." Id. at 30-31. Regardless of the terminology the expert used, the report should have informed plaintiff that the food was "deemed by [the expert] not to be the probable cause." Id. at 431.

Likewise, in Malin, supra, 219 N.J. Super. at 439, we indicated that an expert does not express a net opinion if the jury can draw inferences from the opinion that are not based on mere speculation. See also Callahan, supra, 4 N.J. at 155 ("[T]he evidence must be such as to justify an inference of probability[.]") The terminology used by the expert, therefore, does not necessarily control whether an expert has actually expressed his opinion in terms of certainty or probability.

Tutton explained the probable circumstances of plaintiff's injury in respect of the dangerous condition of the spray gun when it is manually locked open. He stated that the tip must have "[blown] apart" after plaintiff loosened it, given that there had to have been pressure flowing to the tip in order for paint to discharge, which pressure was likely caused by the trigger being locked open in light of plaintiff's testimony that he did not touch the trigger.

Although Tutton did not opine that plaintiff's injury "probably" occurred in the above-described manner, his opinion presented facts that can be interpreted in terms of probability. Tutton explained in his report that based on the design of the spray gun, plaintiff could not have sustained injury unless the spray gun was pressurized, the trigger was depressed, and the tip was open. Because plaintiff stated that he did not depress the trigger, Tutton concluded that the trigger must have been manually locked open by a prior user by way of the allegedly defective feature on the spray gun. Moreover, because plaintiff did not state that paint was discharging from the spray gun prior to his loosening the tip, Tutton deduced that the tip must have been closed.

Thus, Tutton explained the conditions that had to exist for plaintiff to have sustained injury. Under these conditions, Tutton further explained that the spray gun would have been pressurized at the time plaintiff handled it. He examined plaintiff's deposition testimony, which indicated that paint shot from the front and side of the tip; therefore, he deduced "that once this nut was loosened to provide the ability to clean it, it effectively blew apart." Tutton did, however, state that "[t]here would be no way to say" whether plaintiff was injected by the paint flowing from the front of the tip or the side of the tip. He also stated that if the paint had sprayed from the front, the velocity would have been less than presumably the spray that came from the side, perhaps indicating that spray from the front would not have been sufficient to produce plaintiff's injury. In any event, it is not disputed that plaintiff suffered an injury as a result of a high-pressure injection from the spray gun or that velocity was present when plaintiff was injured. Tutton concluded that the manual trigger lock was part of the "general condition of the design of the gun" that "together [with other claimed defects] or in part or any combination thereof" caused plaintiff's injury.

In forensic work, there is generally an inability to state with absolute certainty how an accident occurred. An expert has a device and an injury, and he or she studies the device and formulates a theory about how the accident occurred. In this case, Tutton's explanation about how plaintiff had to have been injured, despite also claiming he does not know how the accident actually occurred, "'express[ed] a reasonably accurate conclusion as distinguished from a mere guess or conjecture.'" Vuocolo, supra, 240 N.J. Super. at 299 (citation omitted). A rational factfinder could conclude from his explanation that plaintiff suffered injury as a result of the allegedly defective manual trigger lock. Tutton expressed that the injury could not have occurred any other way if plaintiff did not touch the trigger, as plaintiff claimed. Tutton had, therefore, opined about more than just possibilities.

Accordingly, Tutton's opinion that the manual trigger lock caused plaintiff's injury was undergirded by facts specific to the way in which plaintiff sustained injury, and expressed in terms of reasonable probability, regardless of the terminology he used. See Johnesee, supra, 174 N.J. Super. at 430-31. Summary judgment, therefore, was inappropriate as to the manual trigger lock.

B. The Self-Activating Trigger Lock and the Tip

We do not reach the same conclusion about the self-activating trigger lock and the tip. An expert does not necessarily have to conduct testing on a product to provide a basis for his opinion about the cause of the plaintiff's injury, Hisenaj v. Kuehner, 194 N.J. 6, 24-25 (2008), but the expert must explain that the risk of injury that could have been prevented is one to which the plaintiff was exposed, see Koruba, supra, 396 N.J. Super. at 526-27.

Plaintiff did not touch the trigger. Thus, even if the spray gun were defective for not having a self-activating trigger lock, plaintiff was not exposed to the risk created by this defect. Therefore, no rational factfinder could conclude that the absence of a self-activating lock caused plaintiff's injury, and summary judgment was properly granted on this issue.

As for the tip, Tutton declined to testify, within a reasonable degree of probability, that each alleged defect in the tip independently caused plaintiff's injury. Causality, according to Tutton, was "possible," and the set of circumstances in which each defect could have caused injury was only "one of a number of things that could have produced the injury[.]" However, there is no evidence indicating how the absence of all of the defects would have prevented plaintiff's injury.

There is also no evidence that plaintiff inadvertently manipulated the tip or the retaining nut, or that the retaining nut had not stabilized the tip; rather, plaintiff testified that he deliberately loosened the retaining nut to remove the tip. Even if the tip had been designed as an unalterable shut-off valve, plaintiff still could have removed the tip while the gun was pressurized and sustained the same injury.

Even if the tip were defective for all of the reasons Tutton expressed, he did not explain that any one or all of these defects could have caused an injury based on plaintiff's version of the accident. Tutton did not opine that the tip was defective because it could be purposefully removed while the gun was pressurized. Without some connection between the alleged defect and the injury, the law does not permit an expert to infer causation merely on the basis that a defect exists. Cf. Froom, supra, 377 N.J. Super. at 317 (finding a net opinion where expert inferred causation from defendants' alleged negligence and not from supporting facts).

Tutton's opinion about causation with respect to the allegedly defective tip is not supported by facts or couched in terms of reasonable certainty or probability. Accordingly, it was a net opinion, Vuocolo, supra, 240 N.J. Super. at 300; State v. Freeman, 223 N.J. Super. 92, 116 (App. Div. 1988), certif. denied, 114 N.J. 525 (1989), and the judge properly concluded that plaintiff failed to prove causation with respect to the tip defects.

We reject plaintiff's contention that the trial court erred by declining to conduct a Rule 104 hearing to determine the admissibility of Tutton's expert testimony. The decision to hold a Rule 104 hearing is within the sound discretion of the trial court. Kemp v. State, 174 N.J. 412, 432 (2002). In Kemp, without conducting a hearing, the trial court granted summary judgment, finding that the opinion of the plaintiffs' expert was not sufficiently reliable under N.J.R.E. 702. Id. at 415, 423. The Supreme Court reversed, finding plain error in the trial court's decision not to conduct a hearing to determine the testimony's reliability. Id. at 432.

Kemp followed Rubanik v. Witco Chemical Corp., 125 N.J. 421 (1991). In Rubanik, the Court stated that when a trial court is "faced with a not yet generally accepted theory of causation," the court should conduct a "hearing to assess the soundness of the proffered methodology and the qualifications of the expert." Id. at 454. A "[p]laintiff's burden is to demonstrate that the methodology used by [the expert] . . . is consistent with sound scientific principles and methodologies accepted in the medical and scientific communities." Kemp, supra, 174 N.J. at 431.

Unlike Kemp and Rubanik, defendant did not challenge the reliability of Tutton's conclusions under N.J.R.E. 702. This case also does not involve a unique causation theory for which it would have been sounder practice to afford plaintiff a hearing. Moreover, a hearing would have been appropriate here if Tutton's grounds for his opinion "were not sufficiently explained and the 'reasons and foundations for them inadequately and perhaps confusingly explicated.'" Id. at 429 (citation omitted). Thus, the concerns that prompted the Court in Kemp and Rubanik to remand are not present here.

Nonetheless, a Rule 104 hearing may be conducted to permit an expert "to identify the factual basis for [an expert's] conclusion." Id. at 427. Here, plaintiff's counsel did not identify which facts Tutton would explain at a hearing. Instead, counsel indicated that Tutton would not explain causation beyond his report and would not state that the alleged defects individually caused the injury. Although counsel indicated that Tutton would state that plaintiff's injuries would not have occurred but for the accident, counsel did not explain how Tutton's support for that conclusion would differ from his deposition testimony. Because counsel did not identify any facts that would come to light in a hearing, the judge properly denied plaintiff's request for a Rule 104 hearing.

Finally, plaintiff's argument that we should remand this matter to a different judge lacks sufficient merit to warrant further discussion here. R. 2:11-3(e)(1)(E).

Affirmed in part, and reversed in part.

1 Tutton rendered the report several months prior to plaintiff's deposition.