The US president has said police acted “stupidly” when they arrested a black Harvard scholar outside his own home.
Prof Henry Louis Gates was held last week in Cambridge, Massachusetts, home to the top university where he teaches.
Barack Obama said the US had a long history of African-Americans being disproportionately stopped by police.
Officers were called to Prof Gates’s house after a woman reported seeing two black males – the professor and his driver – trying to force entry.
Although the exact facts of the incident are disputed, Prof Gates was arrested outside his home after providing the officer with identification.
Mr Obama said: “I think it’s fair to say, number one, any of us would be pretty angry.
“Number two… the Cambridge police acted stupidly in arresting somebody when there was already proof that they were in their own home.”
An initial disorderly conduct charge was dropped and Cambridge police called the arrest “regrettable and unfortunate”.
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