Simply dating someone under age (under 18 in most states) is not a crime. However, a sexual relationship, even if totally consensual is a crime. That is to say, its a crime for a person 18 or older to have sex with someone under age.

Is it illegal to date a 17 year old when your 16?

Although the legal age of consent throughout Australia is either 16 or 17 years of age, legislation in the Australian Capital Territory, New South Wales, the Northern Territory, South Australia, Victoria and Western Australia makes it an offence for a person in a supervisory role to have sexual interactions with a

Is it legal to date a 17 when your 12?

Technically yes but this is trouble waiting to happen. No 12 year old should be dating and no on under the age of consent (which is 16 on PA) should date someone over the age of consent. There are other charges not involving sex that could be brought when the person who is 17 turns 18.