(a) No contract of employment, insurance, relief benefit, indemnity for injury or death entered into by or on behalf of an employee, nor the acceptance of insurance, relief benefit, or indemnity by the person entitled to it constitutes a bar or defense to an action brought to recover damages for personal injuries to or death of the employee.
(b) Upon trial of the action the defendant may set off the sum contributed by the employer toward the insurance, relief benefit, or indemnity paid to the employee, or in case of the employee's death to the employee's personal representative.
(c) Contributions for insurance, relief benefit, or indemnity exacted from or paid by the employee may not be allowed as set off.