From Crimes Act 1900
316 Concealing indictable offence
If a person has committed a serious and indictable offence and another person who knows or believes that the offence has been committed and that he or she has information which might be of material assistance in securing the apprehension of the offender or the prosecution or conviction of the offender for it fails without reasonable excuse to bring that information to the attention of a member of the Police Force or appropriate authority, that other person is liable for imprisonment for 2 years.
Section 345 & 47 of the Crimes Act further states
Abettors and Accessories
345 Every principal in the second degree in any serious indictable offence shall be liable to the same punishment as the principal in the first degree.