LOS ANGELES (AP) — Michael Jackson's doctor is guaranteed to spend the next three weeks in jail awaiting sentencing for the pop star's death.But the amount of time he serves after that could be shortened because of the overcrowded prison system in California.A recently enacted realignment plan diverts nonviolent offenders such as Dr. Conrad Murray from state prisons to county jails to save money and reduce the state prison population.However, law enforcement authorities have said nonviolent offenders could be released earlier to make room for more serious offenders in county lockups.A judge could sentence Murray to a maximum sentence of four years, but it would fall to the Los Angeles County Sheriff's Department to decide just how long he actually spends in county jail, based on time served, good behavior and other factors.