Bryant Furlow reports:

Since the mid-1990s, genetic fingerprinting of HIV strains has helped convict suspects who transmitted the deadly virus to their victims. A genetic “match” between the viral strain infecting rapist and victim is frequently presented to juries and TV audiences with certitude, as a molecular smoking gun. That seemingly compelling piece of evidence is “increasingly determining convictions by criminal courts,” according to six European virologists in the current issue of The Lancet Infectious Diseases.

Mike the mad biologist questions the shady legal implications of that practice:

People are developing ways to sequence the population of HIV viruses, but that creates a whole new set of difficulties: populations of HIV can change rapidly, and, if there's a response to the new patient's immune system, that too can alter frequencies of individual HIV viruses. I don't even know how you definitively in a legal context identify a source with that going on.

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