Justin Bieber -- Former Bodyguard Will Chill ... Behind Bars

The bodyguard who got Justin Bieber in all kinds of trouble will have more than a month to think about his missteps ... in the slammer.

Hugo Hesny copped a plea in his robbery case and got a 45 day jail sentence. He was charged with robbery after allegedly stealing a paparazzo's camera in Atlanta last year.

Hesny was with Bieber a lot during the time the singer went off the rails. Hesny was named in a police report in June 2013 for allegedly attacking a pap in Miami and arrested in December 2013 for allegedly attacking a Florida cop.

Bieber has since cut him loose.