Cory Pierce, The former San Luis Obispo Police Narcotics Detective who was sentenced to 18 months in Federal Prison on extortion charges is set to begin serving his sentence this morning. Pierce pleaded guilty to extortion this past summer. He was sentenced in December. As part of his sentence, he has been ordered to pay $5500 in restitution. According to prosecutors, Pierce took cash and drugs from two people, used drugs on the job, and became addicted to pain killers.