The Commissioner of Veterans Affairs, in his or her discretion, shall investigate all complaints made to the commissioner with respect to the conduct or treatment of veterans, their spouses, or eligible dependents and family members receiving services under this chapter, or any program administered by the Department of Veterans Affairs and for such purpose shall have power to compel the attendance of witnesses under oath. If upon the completion of such investigation, the commissioner finds that any veteran, spouse or eligible dependent has not received proper care or has been ill-treated or abused by any officer or employee, the commissioner shall, in his or her discretion, cause the offender to be prosecuted, disciplined or dismissed and shall order such remedial action as the commissioner deems necessary to eliminate the condition. If upon such investigation, the commissioner finds that no adequate grounds exist for such complaint, the commissioner shall certify that fact to the officer or employee involved and cause such officer’s or employee’s record to be cleared of the incident.