Fair Labor Standards Act (FLSA) - Section 531.40

Where an employer is directed by a voluntary assignment or order of his employee to pay a sum for the benefit of the
employee to a creditor, donee, or other third party, deduction from wages of the actual sum so paid is not prohibited:
Provided, That neither the employer nor any person acting in his behalf or interest, directly or indirectly, derives any
profit or benefit from the transaction. In such case, payment to the third person for the benefit and credit of the employee
will be considered equivalent, for purposes of the Act, to payment to the employee.
FLSA - 531.40 Payments to employee's assignee