Check this out:
Division 477-478 of the Criminal Code Act includes serious computer offences, such as hacking, that can be prosecuted at the federal level. Division 477.1 of the Criminal Code Act:
"(1) A person is guilty of an offence if:
(a) the person causes:
(i) any unauthorised access to data held in a computer; or
(ii) any unauthorised modification of data held in a computer; or
(iii) any unauthorised impairment of electronic communication to or from a computer; and
(b) the unauthorised access, modification or impairment is caused by means of a carriage service; and
(c) the person knows the access, modification or impairment is unauthorised; and
(d) the person intends to commit, or facilitate the commission of, a serious offence against a law of the Commonwealth, a State or a Territory (whether by that person or another person) by the access, modification or impairment."
Also - Cybercrime Act 2001. They are criminal offences not civil, and would be prosecuted by the police. You need to work out what you want out this situation. Have you been sacked or stood down with pay or without pay?