A defendant who intends to offer at trial the defense of insanity or mental infirmity shall file with the clerk of courts not later than the time required for filing an omnibus pretrial motion provided in Rule 579 a notice of the intention to offer the defense of insanity or mental infirmity, and shall serve a copy of the notice and a certificate of service on the attorney for the Commonwealth.
Except as provided in Rule 841, a defendant who intends to introduce expert evidence relating to a mental disease or defect or any other mental condition of the defendant bearing (1) on the issue of guilt, or (2) in a capital case, on the issue of punishment, shall file with the clerk of courts not later than the time required for filing an omnibus pretrial motion provided in Rule 579 a notice of the intention to offer this expert evidence, and shall serve a copy of the notice and a certificate of service on the attorney for the Commonwealth.
Within 10 days after receipt of the defendant’s notice of the insanity or mental infirmity defense, or notice of expert evidence of a mental condition, or within such other time as allowed by the court upon cause shown, the attorney for the Commonwealth shall file and serve upon defendant’s attorney, or the defendant if unrepresented, written notice of the names and addresses of all witnesses the attorney for the Commonwealth intends to call to disprove or discredit the defendant’s claim of insanity or mental infirmity, or mental disease, defect, or other mental condition.
If prior to or during trial a party learns of an additional witness whose identity, if known, should have been included in the notice furnished under paragraphs (A) or (C), the party shall promptly notify the other party’s attorney, or if unrepresented, the other party, of the existence and identity of such additional witness.
No adverse inference may be drawn against the defendant, nor may any comment be made concerning the defendant’s failure to call available witnesses with regard to the insanity or mental infirmity defense, when such witnesses have been prevented from testifying by reason of this rule, unless the defendant or the defendant’s attorney shall attempt to explain such failure to the jury.
234 Pa. Code ยง 568
Committee Explanatory Reports:
Final Report explaining the provisions of new Rule 568 governing notice of insanity or mental infirmity defense and notice of expert evidence of a mental condition published at 36 Pa.B. 700 (February 11, 2006) .
Final Report explaining the July 31, 2013 amendment to paragraph (A) (2) and Comment revisions regarding notice of mental retardation published with the Court’s Order at 43 Pa.B. 4722 (August 17, 2013) .