Someone who gets targetted by prosecutors and charged because he won't a) snitch, b) turn informant, or c) make up information. Despite this pressure, they will maintain their integrity unlike spineless prosecutors.
Prosecutor: You think he will turn informant or just make up information?
FBI agent: What are you f'n stupid cronk? He's a DeMuth.
Prosecutor: You're right. We don't have a case. Let's charge him anyway.
FBI agent: Sounds good. We can always make shit up.
To use the same trick over and over on different people. A trademark maneuver or slight of hand.
She put another date above the date on the check to beat the bad check writing charge. I got demuthed.
1: somebody who maintains their personal integrity under pressure from legal authority
2: somebody who doesn't snitch
3: Alternatively, somebody targeted by the police or legal authorities because they believe he has information that he doesn't really have, and instead of making up information to tell to the cops and get off, takes the consequences like a man
Ex 1: He's hardcore. Not only is he straight edge, he is a DeMuth.
Ex 2: He's a DeMuth; you would squeeze blood out of a turnip before you can get him to snitch.
Ex 3: "Did you hear they charged Jamie with conspiracy?"
"Yeah, they are trying to force him to give up names and make up information."
"That won't happen. He's no curtis jackson; he's a DeMuth."