salary for general laborers

ok i have to ask this question for a friend who has a business. this person has hired employees for a 56 1/4 wk for a salary lets say 750 a week. these employees are only laboring peep which comes to be about 12 hour for 40 hours and 18 for the 16 hours overtime but now on thier checks say salary 56.25 750 now the labor board in fla is trying to get every employee overtime based on 750 for a 40 hour week. can the labor board do this