on probation for unemployment fraud why do i have to drug test

When placed on probation in Florida one of the conditions of probation is that you will submit to random drug screens.  Regardless of the charges you are placed on probation for, per the terms and conditions of your probation you will be subject to random drug screens.  Whether your probation officer chooses to test you is up to him or her.  I would suggest you review the terms and conditions paperwork you signed when you reported to probation.