How can police arrest a person without charge or a warrant?
The police can arrest someone that they have reasonable belief has committed a crime. It is up to the DA to decide to proceed with the charges or to drop them. The one area that the lawyers have not gained total control is the area of mental health. If the police have a reasonable expectation that you may harm yourself or others, they can put a 72 hour hold on you for psychiatric evaluation. Most of the time it takes more than 72 hours so if you really wanted to be out of there, you could file a writ of habus corpus and demand an immediate hearing. By doing that they have themselves given you the ability to plead not guilty due to reason of temporary insanity. The lawyers hate it when the cops haul someone off for a psych evaluation because it really puts a kink in their ability to try the person for a crime.
