Impairment in the general sense means to be under the influence of drugs, alcohol, or some other substance which causes one's physical or mental faculties to perform differently and in a less effective fashion.
In the Duke lacrosse case, the question of impairment came up at various points, primarily on the question of whether Crystal Gail Mangum might have been impaired on the night of the party, either by her own actions or by those of another.
Many hinted or suggested in the media that Mangum might have been given a date rape drug. A urine toxicology test was not performed on March 14, 2006, the date of the alleged attack. However, in April and May, Sgt. Mark Gottlieb made calls to various laboratories inquiring whether they would be able to perform a toxicology test on a hair sample.
Court papers filed on Aug. 31, 2006 revealed that a hair toxicology test had been performed and had found no traces of date rape drugs. It was not revealed which laboratory had done the testing, or which specific drugs they had tested for.
On several occasions, however, Mangum was observed to be impaired by her own voluntary actions. For instance, when meeting with investigators from the Attorney General's office on April 4, 2007, Mangum displayed symptoms of impairment similar to those observed by witnesses and documented on video at the lacrosse party. It was determined that Mangum had taken Ambien, methadone, Paxil and amitriptyline prior to meeting with the investigators.