In Pennsylvania, to guard against undue prejudice in civil cases, evidence of a party’s mere alcohol consumption is inadmissible absent evidence that reasonably shows intoxication. In respect of Blood Alcohol Concentration results, courts found to provide that “[BAC] alone may not be admitted for the purpose of proving intoxication,” but must be accompanied by “other evidence showing the actor’s conduct which suggests intoxication.”  The reasoning was that someone may have alcohol in their system but not be impaired.

This issue was at the forefront of Coughlin v. Massaquoi, where Thomas Coughlin, was killed while walking crossing the street when defendant Ummu Massaquoi crashed into him with her car. Defendant Massaquoi was driving in the left lane of the four-lane road and admitted that she did not see Coughlin prior to the impact. After Coughlin was transported to the hospital and pronounced dead, the autopsy and toxicological testing revealed that Coughlin had a BAC of .313%. Other than this post-mortem BAC result, there was no direct evidence presented to the jury of Coughlin’s intoxication—such as witness testimony that he appeared drunk.  Instead, an expert testified as to impact of that BAC level on an average person.

Although a jury trial found the defendant negligent, it also determined her negligence was not the factual cause of Coughlin’s death. Plaintiff appealed, alleging the court erred by admitting evidence of Coughlin’s BAC without independent, corroborative evidence of his intoxication.

The issue for Pennsylvania’s Supreme Court was whether expert testimony interpreting a BAC result constitutes “other” evidence under Pennsylvania case law, or, if independent eyewitness testimony of intoxication is required before admitting a pedestrian’s BAC. The Court modified the previous standard and held BAC evidence is admissible if the trial court determines that it reasonably establishes a pedestrian’s unfitness to cross the street. The defendant met this standard as she presented an expert who testified to the significant impact a .313% BAC would have on the average person’s coordination, judgment, and self-control—concluding Coughlin was thus unfit to cross the street.

There is no doubt that an important factor in the outcome was the near-poisonous level of alcohol in the pedestrian’s blood, and failing to admit it under such circumstances would have led to a very unfair outcome.

Thanks to Ellis Palividas for his contribution to this post and please write to Mike Bono with any questions.