Now he has apologised - once again - for the latest controversial footage.
He told The Sun: "Facing my mistakes from years ago has been one of the hardest things I've ever dealt with.
"But I feel now that I need to take responsibility for those mistakes and not let them linger.
"At the end of the day, I just need to step up and own what I did."
He said in a statement: "I'm very sorry. I take my friendships with people of all cultures very seriously and apologise for offending or hurting anyone with my childish and inexcusable mistake.
"I was a kid then and I am a man now who knows my responsibility to the world and to not make that mistake again."
Bieber, 20, who has sold more than 15million albums, blamed the first video, filmed when he was 15, on youthful indiscretion.
In the latest footage Bieber wears a blue shirt and a dog tag necklace. A female friend can be heard laughing in the background, and the singer smiles as he gives his twisted rendition of Lonely Girl.
Show business website TMZ reported that the new video was captured when Bieber was 14, after he had seen a comedian's parody of Lonely Girl.
The website also claimed Bieber had realised at the time that making the recording was a mistake, and had told his mentor, the R'n'B star Usher Raymond, and actor Will Smith. Raymond rebuked him and showed him videos to illustrate the evils of racial prejudice, it reported.
Fans in Britain and the US - who call themselves "Beliebers" - left him in no doubt about their dismay last night.
On social media, one, LizaCar, said: "He needs to go back to school, get an education, receive [some] discipline and learn some respect.
"He's out of control and it's not going to have a happy ending the rate it's going."
Jamal Jackson, from Liverpool, wrote: "No I don't care, you know there are certain words you shouldn't use and that's hurtful words against other people. Sorry Justin you can't type a little message on twitter and get out of it!"
Another online commenter branded the baby-faced singer an "arrogant little twerp".
A user calling themselves Disgruntled Reader, from California, said: "The KKK isn't funny, racism isn't funny and using the n-word isn't funny.
"People were terrorized, abused and murdered over the colour of their skin at one time, and making a joke of it is nothing short of breathtaking stupidity and arrogance."
Twitter users in the US mocked the singer by posting a picture of KKK members apparently saying: "We would like to distance ourselves from Mr Bieber. All organisations have a few embarrassing members."
The videos are likely to disappoint the black artists who have worked with Bieber, including Will.i.am, Nicki Minaj and Lil Wayne. Usher Raymond has yet to offer any comments in support of his protegé.
- Daily Mail
