Bruno Mars: Why I Lied to Police After My Cocaine Arrest

Bruno Mars is coming clean in the April issue of GQ magazine. The 27-year-old singer opens up about his 2010 arrest, his unusually chipper mugshot and the difficulties of writing a hit song.

When Mars was arrested in Las Vegas for possession of 2.6 grams of cocaine in September 2010, the "Grenade" singer told police it was his first time using drugs -- but as it turns out, that was a lie.

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"I don't know where that came from. I was really intoxicated. I was really drunk," he admits to GQ. "So a lot of that is a big blur, and I try every day to forget and keep pushing."

But when asked why he had a huge smile on his face in his mugshot, Mars gave a very honest response. "I have no idea ... It was a picture," the artist explains.

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The Grammy-winning singer also confesses to the magazine that songwriting is not easy. "You know how hard it is to write a big song? That s--- is hard, man," he says. "It's so hard to do. Might be one of the hardest things to ever do."

And he was surprised by the success of one of his latest singles, "Locked Out of Heaven." "That one shocked me. That it turned out the way it did," he admits of the No. 1 hit. "I haven't done a song like that. And hopefully every album, I'll get that feeling. And shock the world! Shock the world!"

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Mars also notes that the song, like many on his new album, "Unorthodox Jukebox," is about sex. "It feels good to sing about," he says. "It feels ... sexy. It puts you in a sexy frame of mind. It feels good to project. Sex is a great party starter."

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