Juries in Texas and around the country generally find eyewitness testimony extremely convincing, and witnesses who identify a criminal suspect with a great deal of confidence are especially compelling. However, questions about the way police officers conduct suspect lineups and research into the workings of the human brain have raised doubts about the validity of even confident eyewitness identifications.
Research into the area suggests that accuracy is closely correlated to the speed with which an eyewitness identification is made and the confidence of the identifier. The problem is that witnesses tend to become more confident after making their choices due to confirmation bias and the encouragement they receive from police officers. This means that a witness who was hesitant or unsure during a lineup may appear far more confident when testifying in court.
The conditions under which a lineup is conducted can also influence the outcome. Researchers consider the conditions pristine when the suspect does not stand out in some way, witnesses are told that the perpetrator may not actually be in the lineup, the suspect is not pointed out beforehand, and the lineup contains only one suspect. Creating these conditions in a busy police station can be very difficult, which is a problem because the chances of an accurate identification fall significantly when they are not met.
Attorneys with criminal law experience may approach eyewitnesses with the belief that they are decent people who do not wish to see an innocent person sent to jail. They could then raise doubts by asking questions about the lineup, the conditions it was conducted under and how similar its members looked. Attorneys could also call on experts to explain the shortcomings of eyewitness accounts and identifications to juries. This kind of testimony could be particularly valuable when eyewitnesses have identified a member of a different race.