According to VIC Law for the charge of Refuse drug test - drug driving,

Road Safety Act 1986 - SECT 49

Offences involving alcohol or other drugs

49. Offences involving alcohol or other drugs

(1) A person is guilty of an offence if he or she-
(ca) refuses to undergo an assessment of drug impairment in accordance with section 55A when required under that section to do so or refuses to comply with any other requirement made under section 55A(1);

According to VIC Law for the charge of Refuse drug test - drug driving,
First offence: 12 penalty units

Second offence: 12 months / 120 penalty units

Subsequent offence: 18 months / 180 penalty units

(a) The accused refused to undergo an assessment of drug impairment when required to do so.

(b) The person refused to comply with any other requirement mad under section 55A(1).

(a) Factual dispute.

(b) When the person was asked to undergo an assessment of drug impairment,
more than 3 hours had passed since the person last drove, was an occupant of
or was in charge of a motor vehicle.

Magistrates' Court.