If your main source is court docs and snitch statements, you have to understand most of that is not very credible.
"I am not a snitch," she said during the interview we had the year before she died.
I was humiliated, but also incapacitated by my desire to not be further alienated by becoming a “snitch.”
To Connolly and Morris, Bulger was a TE, or top-echelon informant, the highest designation in the Bureau for a snitch.
They matched up well with us and caught the snitch when it counted most.
He hadn't a notion people would be so low-down as to snitch his idea and go to making cotton gins of their own.
snitch, to give information to the police, to turn approver.
"Now, I'm not going to snitch on my mates," said McCarty decidedly.
The computers I love are being co-opted, used to spy on us, control us, snitch on us.
If anybody tries to stop us or to snitch you free you'll get the acid in those shining peepers without being able to move.
"informer," 1785, probably from underworld slang meaning "the nose" (1700), which apparently developed from an earlier meaning "fillip on the nose" (1670s). Snitcher in same sense is from 1827.
[origin obscure, although apparently these, along with several other slang uses, both British and US, all refer somehow to the long-billed bird and its habits]