The second-highest-ranking officer in the Florida Highway Patrol is stepping down after acknowledging he wrote an email in May encouraging troopers to write at least two tickets per hour.

In the latest fallout from an ongoing investigation into whether troopers were told to meet a traffic-ticket quota, Lt. Col. Michael Thomas, a 30-year veteran and deputy director for the FHP, submitted a letter of resignation on Monday, indicating his last workday will be Friday.