I remember long ago seeing an episode of Cops like that. Police show up and find a man bleeding on the curb. Out of the house runs an incensed woman with a large bloody kitchen knife screaming in unintelligible rage.
Bleedy curb guy mutters near unconscious "I was just trying to get my stuff and leave."

Woman showed the cops a tiny little bruise on her arm that could've been from anything.

Police called EMS, for the guy, said he would spend 48 hours in jail after the hospital released him.

Cops, the show, never did any follow up, but I was left with the impression no assault charges were ever leveled against the stabby bitch.