There are seven episodes that had a hit and run. Two resulted in injuries, four in death, making all of them felonies: - - Monk: Mr. Monk Goes to Mexico (2003)(#2.2), the victim was only injured.
It's a gift... and a curse.
We see Monk constantly ask Captain Stottlemeyer and/or Lieutenant Disher to put out APB's (All Points Bulletins) or BOLOs (Be On the Look Out) to bring suspects and witnesses in. When found the San Francisco Police brings them to the station for Monk and the detectives to interview even though it's pretty clear they didn't want to come. If there is no probable cause for an arrest or an active arrest warrant, the police can't make you go anywhere against your will. Once in a while, a wealthy or educated person will assert this and ask a lawyer to be present but this is rare.