Max George from 'The Wanted' -- Justin Bieber's a 'Lovely Lad'

Justin Bieber gets a bad rap ... so says The Wanted's Max George who tells TMZ the singer is actually a "lovely, lovely guy."

George and his Wanted bandmate Thomas Parker were stumbling down Sunset Blvd. last night (don't worry, they're old enough to booze) ... when we had a great drunken convo with the guy.

Among the highlights -- George says he would love to be a judge on "American Idol" one day, except he's in a boy band so, "I'm not sure anyone would respect my opinion."

Max also defends his pal Bieber -- saying, "I've met Justin and he's a lovely lad and people make the wrong opinions of him."

Sure, JB seems like a nice enough guy ... when he's not spitting on people (allegedly), pissing off his neighbors (allegedly) or urinating in mop buckets (definitely).