2 attorney answers No, its not illegal. However, it would be extremely stupid for a 20 year old male to date a 15 year old girl. Thats because she could tell everyone that they had sex, even though they didnt, and all of the sudden the 20 year old males reputation

Is it illegal for a 15 year old to date a 23 year old?

A 23 year old man can date a 15 year old girl without violating any laws. Kissing does not violate any laws.

Can a 17 year old go to jail for impregnating a 15 year old?

If the statutory-rape law makes the sex illegal and makes the crime punishable by a jail sentence, then yes, a jail sentence is possible though not certain. A 17-year-old would serve the sentence in juvenile hall until turning 18, then transfer to an adult jail. There is no defense to a charge of statutory rape.