Jailhouse Snitches and Prison Rats
Jailhouse snitches are inmates that give authorities information about other inmates in city or county jails. Prison rats are their state or federal prison counterparts.
*Tip - If you search for a first and last name but find nothing, try one or the other and page through the results. This is old tech which searches for exact matches. You could also try typing the first name into the box and looking for suggestions.