I'd heard that false rape accusations were a lot more common

than generally known, but had no idea it was this bad:
A study of rape allegations in Indiana over a nine-year period revealed that over 40% were shown to be false — not merely unproven. According to the author, “These false allegations appear to serve three major functions for the complainants: providing an alibi, seeking revenge, and obtaining sympathy and attention. False rape allegations are not the consequence of a gender-linked aberration, as frequently claimed, but reflect impulsive and desperate efforts to cope with personal and social stress situations.” ( Kanin EJ. Arch Sex Behav. 1994 Feb;23(1):81-92 False rape allegations. )
...
Craig Silverman, a former Colorado prosecutor known for his zealous prosecution of rapists during his 16-year career, says that false rape accusations occur with “scary frequency.” As a regular commentator on the Bryant trial for Denver’s ABC affiliate, Silverman noted that “any honest veteran sex assault investigator will tell you that rape is one of the most falsely reported crimes.” According to Silverman, a Denver sex-assault unit commander estimates that nearly half of all reported rape claims are false.

Found this linked at Insty, who also had a link to this at Althouse. This boils down to one of the classics of false accusation: after screwing with five guys in a bathroom, her boyfriend sees her right after and rather than face the music she says she was raped. And if one of the dumbasses hadn't recorded some of it, they'd probably be looking at prison unless she broke down and recanted; a doubtful happening. And that's assuming the prosector isn't a Nifong type who'd try to push it anyway.