I think the criticism of "forensic science," generally in the linked Popular Mechanics article is overblown. Much forensic science is very good.
Fingerprints can be matched by computer. The only real dispute there is partial print matches. There was a scandal regarding very poor fingerprinting techniques; there have also been a couple of incidents of outright fraud. But if the prints match, dude, it's you. And there are many competent fingerprint examiners. I've never seen a computer mismatch out of thousands of examples.
I have some expertise in collision reconstruction. It's certainly true that some techniques used are not as good as others; expressing solid confidence in pedestrian throw is probably a bad idea. But collision reconstruction based on critical speed scuff marks and various other methods are solid physics.
Forensic accounting is valid science. Forensic chemists test for drugs and alcohol with very high accuracy. Properly done ballistics testing is good science. Hair sample comparisons are good science, if not oversold. DNA is good science, but not if you screw up your Bayesian analysis.
Some people testify to silly things. Some people make mistakes. Some people are willing to say things they know aren't true. Some scientists are underqualified. Some fields - like forensic odontology - lack the rigor of others, and should not be allowed in court barring a prior showing that the person can do what they say they can do.
But the idea that forensic science is "mostly created by cops who were guided by little more than common sense" seems quite misguided to me.
I've heard that, until relatively recently, forensic arson investigation was actually complete nonsense.
We're all familiar with false popular memes that spread faster than they can be stomped out: You only use 10% of your brain. Al Gore said he invented the internet. Perhaps it doesn't surprise you that some memes in popular culture can't be killed. But does the same thing happen in science?
Most of you have probably heard of Broca's aphasia and Wernicke's aphasia. Every textbook and every college course on language and the brain describes the connection between damage to these areas, and the speech deficits named after them.
Also, both are probably wrong. Both areas were mistakenly associated with their aphasias because they are near or surrounded by other areas which, when damaged, cause the aphasias. Yet our schools continue teaching the traditional, erroneous story; including a lecture in 9.14 at MIT given in 2005. Both the Wikipedia entry on Wernicke's aphasia and the Wikipedia entry on Broca's aphasia are still in error; the Wikipedia entry on Wernicke's area has got it straight.
Is it because this information is considered unimportant? Hardly; it's probably the only functional association you will find in every course and every book on the brain.
Is it because the information is too new to have penetrated the field? No; see the dates on the references below.
In spite of this failure in education, are the experts thoroughly familiar with this information? Possibly not; this 2006 paper on Broca's area by a renowned expert does not mention it. (In its defense, it references many other studies in which damage to Broca's area is associated with language deficits.)
So:
References
Bogen JE, Bogen GM (1976). Wernicke's region—Where is it? Ann. N. Y. Acad. Sci. 280: 834–43.
Dronkers, N. F., Shapiro, J. K., Redfern, B., & Knight, R. T. (1992). The role of Broca’s area in Broca’s aphasia.
Journal of Clinical and Experimental Neuropsychology, 14, 52–53.
Dronkers NF., Redfern B B., Knight R T. (2000). The neural architecture of language disorders. in Bizzi, Emilio; Gazzaniga, Michael S.. The New cognitive neurosciences (2nd ed.). Cambridge, Mass: MIT Press. pp. 949–58.
Dronkers et al. (2004). Lesion analysis of the brain areas involved in language comprehension. Cognition 92: 145-177.
Mohr, J. P. (1976). Broca’s area and Broca’s aphasia. In H. Whitaker, Studies in neurolinguistics, New York: Academic Press.