He's not in prison, he's in jail, and there's a big difference.
Depending on the circumstances, you could sit in jail your whole life while you await some technical process to complete. You don't even have to be charged with anything.
What?! Jail and prison are synonyms. There is no real difference.
http://www.oxforddictionaries.com/definition/english/prison - A building to which people are legally committed as a punishment for a crime or while awaiting trial.
http://www.oxforddictionaries.com/definition/english/jail - A place for the confinement of people accused or convicted of a crime.
Both refer to being detained both before and after conviction.
Jails are also usually less well funded, older, and generally less pleasant (oh yeah) than are prisons.
A concise summary:
http://sheriff.org/faqs/displayfaq.cfm?id=4f892698-5c5d-40f8...