Armed with a roll of stickers and GoPro cameras, Mark Thompson and his crew patrolled the Sports Castle Lofts construction site at Broadway and 10th Street near downtown Denver. The team calls itself the “Payroll Fraud Task Force,” aimed at rooting out wage theft and employee misclassification at job sites across Colorado. On a recent September morning, the team talked up workers on their lunch break, asking if they’re being paid correctly and on time.