Physical evidence, such as DNA and fingerprints, are not a legal requirement in a criminal prosecution. As a former prosecutor, I have presented juries with many cases involving little to no physical evidence. In the absence of physical evidence, prosecutors rely solely on the testimony of witnesses. Eyewitnesses - those who stood by and watched a crime occur - or victims - those who had crimes committed upon themselves - provide their testimonies as evidence.
A video to which I have posted a link below talks about the problems associated with eyewitness testimony and how the mind does not recollect and recall information with great accuracy.
Unfortunately, many people are convicted each year in Florida and nationwide solely on the testimony of eyewitness testimony.
Check out the link below to hear an interesting discussion about eyewitness testimony from a skilled forensic psychologist.
Eric Matheny is a criminal defense attorney representing clients in Miami-Dade and Broward.