Justin Bieber has rejected the plea deal prosecutors in his Miami Beach DUI case have offered ... and a big reason is because he doesn't want random drug testing...he says he'll take his chances at trial

So Matt bet Billy $20 that Justin Bieber WILL NOT go to trial...CLICK HERE to listen!

Who will win the bet???

News Photo: Justin Bieber attends Ciroc party at Vanquish Lounge…

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