The decision comes four days after he pleaded guilty in Saline County District Court to resisting arrest and public intoxication in a June incident at a Benton restaurant.
His retirement date is October 1, according to a letter Pennington has sent to Saline County Judge Lanny Fite and the Quorum Court dated today.
After his court appearance on Monday, Pennington also asked for forgiveness, saying "forgive me for my poor judgment."
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