"Eyewitness testimony, once considered the gold standard of evidence, can often result in wrongful convictions. Of those who have been exonerated by DNA evidence, it's estimated that faulty eyewitness testimony is responsible for almost three-quarters of wrongful convictions. That includes Royal Clark Jr., a Louisiana man who spent 17 years behind bars simply because he looked like a serial robber. ""48 Hours"" correspondent Erin Moriarty reports.
