A common method for authorities to identify the perpetrator of a crime is the use of a photo lineup. In a photo lineup a witness is shown many photos of people, including the person accused of committing the crime. Included in the group of photos are innocent people who have a similar physical description of the potential criminal. This is done so the witness isn't provided with only an image of who the authorities suspect to be guilty. Naturally there is a margin of error in using such a method but eyewitnesses provide a strong tool for law enforcement to identify criminals.
Improving the reliability of eyewitness identification is paramount to ensuring that people are not wrongly accused of crimes they didn't commit. Sadly, however, people are continually being charged and convicted for crimes they didn't commit, often on the bases of faulty eyewitness testimony. Eyewitness testimony can be persuasive in the courtroom but is often unreliable.
Gary Wells, a psychology professor at Iowa State University, believes eyewitness misidentification is the greatest cause of wrongful convictions nationwide. He has produced a study that shows the method which a witness is shown photos can influence the accuracy of identifying the correct individual. The study found that photos shown sequentially - one at a time, one after the other - rather than shown together as a group will produce more consistent, accurate results.
According to this study, witnesses use a more absolute comparison of each photo with the sequential method. The witness is forced to process the photo individually and create an opinion more independently - and is therefore less likely to make a misidentification.
The study illustrates that using a sequential method prevents less of a comparison between photos in a group where a witness often tends to compare the lineup members to each other to identify who looked most like the perpetrator. Many times witnesses, in an effort to simply be helpful, will make their decision based on who they "thought" the person "might be."
An innocent person can sometimes pay the consequences when an eyewitness is simply trying to do the right thing while unknowingly accusing the wrong person. If you are facing charges for a crime you didn't commit, contact an experienced criminal defense attorney to defend your rights.