I did a 2 second google search, and no, in victoria they can't randomly search you except when a) they're searching for weapons in a designated place and time or b) the police commissioner gives written approval for a search to take place in a given place and time.
Has anyone here ever watched The Force? Every single one of the searches that I've seen on that program has been CONSENTED to by the person being searched. The officer will come up to them while putting on gloves (giving the impression that a search is going to take place) and then ask if it's alright if they take a look in the car. Most people don't realise that they are actually asking for your consent, and you don't have to give it.
Q.9 In what circumstances are the police allowed to search me?
(a) Police can search you, your bags or your car without a warrant if they suspect on
reasonable grounds (
that means they have to have some kind of actual evidence or reason, it can't be random) you have drugs of dependence, weapons, volatile substances (if you are under 18), or a graffiti implement. They can also search you if you are the target of an authorisation or in an authorised zone under state terrorism laws. From time to time Parliament passes laws specific to events that increase police search powers.
(b) Police can search you if they have a search warrant that permits the search of persons.
(c) Police can search you if they have arrested you, but only to the extent necessary for safety or the location of items connected to a crime which they have reasonable grounds to suspect are in your possession.
(d) From 16 December 2009 - the police have new search powers under the Control of Weapons Act that allow them to search any person or car in a planned or unplanned designated search area without grounds to suspect that person may be carrying weapons. The Police must give 7 days notice of a planned designated search area by publishing the notice in the Government Gazette and a Newspaper. The Chief Commissioner may declare an area to be an unplanned designated search area at any time in writing. Search areas can be designated for 12 hours at a time. Within designated search areas, anyone can be searched without reasonable grounds. It has been acknowledged by the Government that these powers are incompatible with human rights as they arbitrarily infringe the right to privacy.
When police act under their designated search powers they must provide a written notice of the source of the power and that it is an offence to hinder them from searching under these powers.
If a person requests - the police must provide a written notice stating their name, rank and place of duty.
The search conducted is for the purpose of identifying, seizing and detaining weapons.
Q.10 How can the police search me?
There are two kinds of searches police can do:
a) Pat down search
b) Full search (includes where absolutely necessary a strip search and on occasions a cavity search).
Searches are extremely invasive and humiliating. Searches have the potential to engage many sections of the Charter of Human Rights. Where they are not lawful, they are an assault and in the case of strip and particularly cavity searches, a sexual assault. For this reason, the law only permits them where there are lawful grounds and then only to the extent necessary. Your privacy is a key issue in searches. As a result searches must be conducted in private and where at all possible by some as of the same sex as you. Where your sex is not determined, it is up to you to decide.
If police do not have the power to search you, they can do so with your written permission. This means you can and should say no if you feel at all uncomfortable.
This is all from
http://www.communitylaw.org.au/flemingtonkensington/cb_pages/policepowersandmyrights.php
I recommend everyone reads it, as there's a lot of misinformation and rumour surrounding this stuff.