People have been warned to be careful when talking themselves up on dates as Australia’s biggest state considers law reforms that would mean sexual consent obtained through lying would be invalid and potentially lead to lengthy prison terms.

The New South Wales Law Reform Commission has recommended reforms to the state’s laws on consent, including: "We propose that the law should provide that a person who is fraudulently induced to participate in sexual activity does not, in law, consent to sexual activity."

Fraud invalidates consent in all Australian jurisdictions, but usually under particular circumstances.

Sydney University criminologist Andrew Dyer told 10 Daily that the proposed New South Wales reform is “quite dramatic in its reach”.

“It means you would have to be very careful in talking yourself up,” he said, adding that “a lot of people would say that’s a good thing”.

The New South Wales Criminal Code already holds that sexual consent is not valid if given under a mistaken belief as to the identity of the other person, or a mistaken belief that the other person is married to the person or the sexual activity is for health purposes, or any other mistaken belief about the nature of the activity induced by fraudulent means.