Justin Bieber allegedly couldn't walk in a straight line when he was arrested last month.

New video footage, released by Miami-Dade County prosecutors after it was sought under Florida's public records law, shows the 19-year-old star stumbled slightly while trying to prove he was sober and spent some of his time in jail doing push-ups, before being charged with driving under the influence (DUI), driving with an expired licence and resisting arrest.

A law enforcement source told gossip website TMZ.com that some of the nine hours of video surveillance show Justin, who was filmed wavering as he tried to walk heel to toe on white line and reaching his arms out to steady himself, was under the influence at the time, even though his blood alcohol level was barely measurable at .014 and he did 23 push-ups in 28 seconds before he was released on bail.

The 'Believe' singer's lawyers persuaded the judge overseeing the case not to release four clips that show Justin in ''various states of undress, which show personal parts,'' captured while he was giving a urine sample.

A source, who saw the footage, said: ''Justin is seen several times stumbling around while he was taking his tests. As if he had a problem with his balance ... [the video] also shows Justin taking his various tests and eventually taking a p**s.

''The stumbling and going to the bathroom is obviously reason enough for his attorneys to request it be sealed ... If I was trying to paint a picture that my client was innocent ... I wouldn't want a video of him stumbling around and looking out of it to go public either.''

The 'Heartbreaker' hitmaker is set to appear in court in Miami next Monday (03.03.14), after reportedly rejecting a plea deal that required him to submit to random drug testing for up to nine months and complete 40 hours of community service.