The Superior Court has decided the case of Commonwealth v. Diehl, No. 258 MDA 2015 (April 28, 2016), holding that it was not error for the trial court to allow the Commonwealth to introduce evidence of Diehl’s 2005 Pennsylvania DUI conviction and subsequent, related education classes at his current trial.


Appellant, Matthew Scott Diehl, was sentenced to 9 1⁄2 to 19 years after a jury convicted him of Homicide by Vehicle while DUI, Homicide by Vehicle, Accidents Involving Death or Personal Injury, DUI General Impairment 3rd, Duty of Driver in Emergency Response Area, and DUI High Rate 3rd. The trial ended with a jury verdict of not guilty on the count of Third Degree Murder, but guilty verdicts on Homicide by Vehicle- DUI and all other counts.

Diehl’s charges stemmed from an accident wherein he struck and killed an emergency responder who was setting up a roadblock for a lifeline helicopter to land near an accident scene. Diehl left the scene after striking the victim.

After being arrested and charged, he went to trial. Before trial, the Commonwealth filed a Motion in Limine seeking to introduce evidence of Diehl’s 2005 and 2007 DUI convictions and alcohol awareness education classes. The trial court deemed that Diehl’s 2005 DUI conviction and education evidence relevant and admissible to prove malice, criminal negligence, and recklessness by showing Appellant disregarded the specialized knowledge he had acquired regarding the increased risk of danger that drinking after driving poses.

At Diehl’s trial, the Commonwealth and defense entered into stipulations regarding the Diehl’s 2005 DUI conviction and subsequent DUI education classes. The trial court thereafter allowed the Commonwealth to present evidence of the 2005 Pennsylvania DUI conviction, but only to the extent it showed the Appellant took classes focused on the dangers of drinking and driving.


Did the trial court commit error when it allowed the Commonwealth to introduce evidence of Diehl’s 2005 DUI conviction and alcohol awareness classes as evidence of malice in support of the Third Degree Murder charge?


No. The probative value of Diehl’s 2005 DUI conviction and participation in DUI classes exceeded its potential for prejudice and there was no reversible error in the court’s evidentiary ruling.


The Superior Court first reviewed the applicable Rules of Evidence regarding bad acts or crimes stating that under the Pennsylvania Rules of Evidence, evidence of other bad acts or crimes that are not currently being prosecuted against the defendant are not admissible against the defendant to show his bad character or propensity to commit criminal acts. However, evidence of other crimes may be admissible where that evidence is used for some other purpose. Such purposes explicitly include “proving motive, opportunity, intent, preparation, plan, knowledge, identity, absence of mistake, or lack of accident.” However, admission for these purposes is allowable only whenever the probative value of the evidence exceeds its potential for prejudice.

The Commonwealth contended that the other crimes evidence was admissible in Diehl’s case under the exceptions regarding knowledge and intent (malice), as well as absence of mistake or accident. More specifically, . . . the aforementioned evidence established that Diehl had specific knowledge, experience and training concerning the risks of driving while impaired, and Diehl chose to consciously disregard those risks, thereby demonstrating that he acted with malice and an absence of mistake or accident.

In finding that the trial court committed no error, the Superior Court was persuaded by the “nearly unanimous” extra-jurisdictional decisions that prior DUI offenses and DUI education programs are admissible to establish the mens rea of third-degree murder or vehicular homicide.

The Superior Court noted that the evidence was offered here to as a means to infer Diehl’s state of mind leading up to and including the time of the accident. His past experience with DUI and leaving the scene of an accident, and the special instruction he received on the dangers of drinking and driving were, therefore, highly probative to the question of whether he, more than the typical driver, knew better than to drink and drive and to leave the scene of any accident.

Additionally, the trial court tempered any potential for unfair prejudice by instructing the jury that the evidence was admitted for the “very limited purpose” of tending to show what Diehl’s knowledge was of the hazards of drinking and driving.

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