Next time you see one of those television crime-scene investigators crack a case with high-tech analysis, better take it with a grain of salt. The National Academy of Sciences, the nation’s most prestigious scientific organization, has surveyed the field of forensic science and found it grossly deficient.
It’s not just that many forensic laboratories are poorly funded and staffed with “experts” who are poorly trained. The more fundamental problem, according to the study, is that there is little evidence of the accuracy and reliability of most forensic methods — especially those that rely on expert interpretation.
The most thoroughly validated technique is nuclear DNA analysis, which has a minuscule likelihood of error when done right. But other well-known methods that can supposedly identify a guilty person or link a weapon or other evidence to a particular crime have no rigorous scientific proof that they work consistently.