Kevin Johnson posted a lengthy statement Saturday night, calling the situation "disheartening" and that it led to a "reprehensible" outcome.
Videos posted online show police handcuffing the two men Thursday. Philadelphia's police commissioner said Starbucks employees called 911 to say the men were trespassing. He said officers did nothing wrong and the men refused to leave, leading to the arrest.
Johnson said it was wrong for the store to call police and he will make any "necessary changes to our practices" and "you should expect more from us."
He said he'll be joining Philadelphia's regional Starbucks manager in the coming days.