I'm pretty sure it was intended in the sense of "to finger a suspect" (cf git blame) rather than anything vulgar.
I think the tendency to take anything, in nearly any context, that could even maybe be vulgar, as vulgar 100% of the time, is actually relatively recent.
No I mean just refusing to let any mention of some normal use of a word go without taking it that way. I'm reasonably up on my Shakespeare (LOL "up on" LOL) so I know of the joys of double entendre and innuendo. It just seems like any innocent word or phrase that could be taken that way now must be avoided in a way that it didn't have to be as recently as 2-3 decades ago—which is a source of a good deal of humor for us now, as we mine historical media for things unavoidably funny to the modern, finely-tuned-to-spot-imaginary-sexual-references-in-everything mind, despite (often—not always) the same slang being in use back then.
