Brown has permission to attend the three-hour event on 1 p.m. until 4 p.m. in West Hollywood on Sunday, but as soon as the event is over, he must return to the Malibu rehab facility.
The facility will also be drug testing Brown when he returns, TMZ said.
Brown, who is accused of abusing singer Rihanna, avoided jail time due to his progress in anger management rehab.
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