"American Idol" finalist Jacob Lusk threw himself at the mercy of a court back in November, begging a judge to end his probation from a 2009 arrest so he could compete on "American Idol," TMZ reports.

It all started back in February 2009 when cops cited Jacob for riding on an Los Angeles. metro train without buying a ticket. 

Jacob blew off his court hearing and an arrest warrant was issued.

Fast forward to Nov. 2010, a day after Jacob auditioned for "Idol" and got his golden ticket to Hollywood. Lusk was pulled over for a traffic stop. The cop discovered the warrant and arrested him.

Jacob went to jail and then to court the next day and pled no contest to the train-hopping charge.  He was sentenced to three days in jail and two years probation.

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Jacob served his time and then went back to court, telling the judge "Idol" wouldn't let him on the show if he was on probation.  After his emotional plea, the merciful judge terminated his probation.

Fun Fact: On night one in the pokey, Jacob sang to 170 inmates, who liked it a lot.  Thing is, the guard wasn't a fan, screaming through the loud speaker, "This isn't a f***ing singing contest."

Undaunted, Lusk sang over the next day-and-a-half, preparing for "Idol," And on his last day, Lusk sang a farewell song.