is making out in a car a crime

Short answer: not inherently, but if the public can see you, expect a chat with the constabulary.

Across Australia, anything sexual that’s visible to the public can attract offences like offensive conduct or indecent exposure—so a parked car on a public street with steamed-up windows isn’t a magic invisibility cloak.

On private property and out of public view, consensual adults usually won’t have a problem; just keep it safe, sane, and definitely not while the car is moving.

Also mind the booze: even parked, being over the limit with keys in the ignition can land you in strife; be discreet, park legally, and you’ll likely avoid turning date night into a court date.