To be put in jail, you must have killed at least 3 people, be on the wanted list and be beaten in a battle by a police officer. Sentences last for how many kills you had. The least is 3 days. If you confess and turn yourself in, your time in jail will be half it should be. You may make bail to get someone out but you cannot make bail for yourself. Bail is based on double of how many days you are in. Say you are in for 3 days, someone must pay 6,000 zenni to bail him/her out. To be put on the wanted list, your karma must be below -5. A wanted convict may not turn down a challenge by anyone. Once you die or busted, you are taken off the wanted list and karma returns to 0.