SPRINGFIELD — A former prosecutor’s special police force made numerous arrests and seized hundreds of thousands of dollars in drugs and cash from traffic stops.It also led to allegations of money mismanagement and, this morning, was deemed unlawful by a majority of the state’s highest court.The Illinois Supreme Court ruled today that the LaSalle County State’s Attorney’s Felony Enforcement Unit, a unit created by ex-state’s attorney Brian J. Towne to root out drugs on Interstate 80 …