LOS ANGELES (AP) - A judge wants more information on Chris Brown's probation after he tested positive for marijuana on a random drug test.

Los Angeles Superior Court Judge Patricia Schnegg says Brown produced a medical marijuana prescription from California, but he tested positive in Virginia.

She says while she didn't order Brown not to use drugs, Brown needs to be careful about his public image, especially with kids.

Schnegg says she also wants more information on Brown's community service logs, which she calls "somewhat cryptic."

Brown is on probation for beating up Rihanna in February 2009.