Maryland Health - General Section 5-509
(a)   Any individual who is 18 years of age or older may decide the disposition of the individual's own body after that individual's death without the predeath or post-death consent of another person by executing a document that expresses the individual's wishes regarding disposition of the body or by entering into a pre-need contract.
(b)   In order to be valid, any document executed under subsection (a) of this section must be written and signed by the individual in the presence of a witness, who, in turn, shall sign the document in the presence of the individual.
(c)   Unless a person has knowledge that contrary directions have been given by the decedent, if a decedent has not executed a document under subsection (a) of this section, the following persons, in the order of priority stated, have the right to arrange for the final disposition of the body of the decedent, including by cremation under § 5-502 of this subtitle:
(1)   The surviving spouse of the decedent;
(2)   An adult child of the decedent;
(3)   A parent of the decedent;
(4)   An adult brother or sister of the decedent;
(5)   A person acting as a representative of the decedent under a signed authorization of the decedent;
(6)   The guardian of the person of the decedent at the time of the decedent's death, if one has been appointed; or
(7)   In the absence of any person under paragraphs (1) through (6) of this subsection, any other person willing to assume the responsibility to act as the authorizing agent for purposes of arranging the final disposition of the decedent's body, including the personal representative of the decedent's estate, after attesting in writing that a good faith effort has been made to no avail to contact the individuals under paragraphs (1) through (6) of this subsection.
(d)   (1)   Subject to paragraph (2) of this subsection, if a decedent has more than one survivor under subsection (c) (1) through (4) of this subsection, any adult child, parent, or adult brother or sister of the decedent who confirms in writing to a practitioner that all of the other members of the same class have been notified may serve as the authorizing agent for purposes of § 5-502 of this subtitle unless the practitioner receives a written objection to the cremation from another member of that class within 24 hours.
(2)   If a decedent has more than one survivor under subsection (c)(1) through (4) of this section, the majority of a class may serve as the authorizing agent.
(e)   In the case of an individual whose final disposition is the responsibility of the State or any of its instrumentalities, a public administrator, medical examiner, coroner, State-appointed guardian, or any other public official charged with arranging the final disposition of the decedent may serve as the authorizing agent for purposes of § 5-502 of this subtitle.
(f)   In the case of an individual who has donated the individual's body to medical science or whose death occurred in a nursing home or other private institution, a representative of the institution to which the body was donated or in which the decedent died shall authorize cremation for purposes of § 5-502 of this subtitle if the decedent executed cremating authorization forms and the institution is charged with making arrangements for the final disposition of the body.