Prison break
Background:
The harshest penalty that a criminal can get is the high jailtime associated with leading an active life of crime. Prison breaks have always been suggested in one shape or form, but I think the time has come to finally make one because criminals are now able to pay jail fines and thus get out of jail, so we've already allowed for that.
Regular criminal events have the potential to earn you enough money to always pay your jail fine if you sell a lot of your drugs. Well, why not make prison breaking a reality now that criminals can get out of jail already? This new feature would make it accessible for poor or greedy criminals to get out of jail for free (except ammo and medkits costs).
Details
Prison breaks are either automated or arranged by Crimbosses. I suggest Crimbosses to develop the metagaming aspect, so let's go with that. The Crimboss has special privileges and can start a prison riot by standing on a marker in the jail. This will initiate a 300 second timer (5 minutes) and people in the prison have to use the "riot" animation to join the prison break (maybe not if it's too difficult to script) or they could simply stand in a particular room of the prison.
The riot will begin when the time is up and criminals have to use their fists to break down various gates until they enter the weapons depot. Cops can prevent them from doing this, but they should only be able to use fists (which doesn't make much sense), so perhaps they should not be able to defend the gates. Cops can use this extra time to regroup. After the cops reach the weapons depot and get access to their weapons, a series of prison hallways will follow and criminals will have to fight cops along the way. The 3rd main objective for criminals is to burn the prisoner records archive. Cops will receive money and arrest points from preventing the criminals in escaping, but criminals will only get their freedom and money for every kill (4000).
Criminals will receive added jailtime (1.5x or 2x as much as a normal criminal event). If criminals are successful in killing enough cops and breaking through, they will receive their freedom, but they will also lose their wanted level because they would have burned the prisoner records archive in the process (there isn't much point in escaping if you're just going to get killed in the water a few minutes later and it would be too difficult.)
Criminals will now have to swim back to Los Santos, lol. I realize some might use /kill, but perhaps a respawn point should be added outside the prison, so that tactic wouldn't work.