From 2001-2012, Cosner was accused of misconduct 15 times and skipped five court hearings involving the complaints. He was reportedly disciplined with verbal warnings and write-ups a handful of times. The allegations include "offensive conduct/language" in 2007, sleeping on the job in 2011 and in 2006 he was suspended for violating "courtesy and respect" rules, holding secondary employment and receiving "unlawful compensation."
Cosner's past could come back to haunt him in the Bieber case, in which the Canadian pop star is accused of driving under the influence, resisting arrest and operating a vehicle without a valid license.
According to Cosner's police report, Bieber was drunk and drag racing through Miami. However, surveillance footage, GPS documents and the result of the singer's breathalyzer test exposed untruths in the officer's recount.
Bieber wasn't drunk or speeding when he was arrested. The 19-year-old was going 27 MPH — while cops followed him down a Miami street — and his blood alcohol level was .014. Toxicology reports did confirm that the "Confident" crooner had marijuana and prescription drugs in his system.
While Cosner was later cleared in seven of the misconduct cases, sources say Bieber's lawyer plans to call his credibility into question.
A trial date for the DUI case has been set for March 3.
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(Photo: AP Photo/Miami Dade County Jail)