It's hard to keep track of Chris Brown's legal run-ins since his assault of Rihanna in 2009, but this part's easy: He is now in jail, reports CNN. Brown was taken into custody yesterday after a Malibu rehab facility kicked him out, putting him in violation of his probation. It's not clear what Brown did to get the boot, but TMZ doesn't think it involves drugs, violence, or the "inappropriate relationship" he was found to be having with a female staffer earlier this month. Nor is it clear how long he will have to remain in jail, but his next court appearance isn't until Monday, reports AP. Brown had been in the rehab facility for about four months, after he got arrested on assault charges in DC and later hurled a rock through a window of his mother's car.