Since chances of escaping jail on your own are very slim, you should be able to buy a tool (screwdriver) which will increase the chances of you successfully breaking out of jail. You could have a maximum of 1 screwdriver in your inventory. You can buy this screwdriver at a gas station or 24/7 for a fixed price which admins can set. Say there is a 50% chance of you escaping with a screwdriver, if you fail, you lose the screwdriver. If you escape you also don't have it anymore