This game referring to its Name is talking about Crimes - and there are many different crimes way such as Robbery - kill - pimp ... Etc.,
each of that characters can go to jail for this Crime.
So, what about Tricking other! Didn't it consider a crime?
My Suggestion is about (Imposter)
It can be an Event - Something like [ Imposter is in Town today for the next 10 days - You can invest your Money, Credit with him and he will Double your investment - or maybe giving you 50% Profit, just beware from him and do it wisely]
and after 2-3 days after some people invest and get a huge profit and other Invest (daily or every 2 days invest)
[ The Imposter Escaped from The Town with all last people invest and all the crime city is looking for him] that happened Randomly before the 10 days
for a test, you can make a limit for investing with Imposter
Best Wishes <3
DeadLy