Yes it is fair. The 17 year old male should have thought of the consequences before acting upon anything. It is his fault for having sex with a 15 year old, who is a minor. He knew the outcomes, and he could have dated or have a girlfriend the same age as him - to have sex with or whatever. This is considered as rape. More specifically, statutory rape. This is one of the 'crimes' that people can get high penalities for.
All states have an "age of consent," or an age at which a person can legally consent to sexual activity and can then no longer be a victim of statutory rape. Some states also have laws that look at the age difference between the two people as well as their individual ages. All states have laws that have restrictions on the relationship between the two people, changing the age of consent, or the penalty, for sexual relations between a person of authority, such as a teacher, assistant coach, or tutor. These laws change, and can vary depending on other circumstances.
To make things confusing, what if a minor and an adult were to wed? And they were having sex? Would that still be legal?
For example, Matthew Koso. He married a 14 year old girl. I believe he was 22 at the time.
Here's the link to that story:
http://abcnews.go.com/GMA/story?id=1121138&page=1
For those people that think adult females having sex with underage males is discriminatory, because there used to be no law about it. Here's information to clear that up.
In the past, sex involving an adult female and an underage male was often ignored by the law, as many believed that this was not a traumatic or negative experience for teenage boys.However, in recent years, social perceptions have shifted, particularly when the adult female is in a position of responsibility, and there have now been a number of high profile cases (Mary Kay Letourneau, Debra Lafave, Tammy Imre, Pamela Rogers Turner, Pamela Smart) where adult females have been prosecuted for participating in sexual relationships with younger males. These cases mentioned have all involved adult female teachers and young teenage male students.
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I believe this law exists to prevent adults taking advantage of minors. Some of the adults manipulate their 'younger' boy/girlfriends into having sex. Parents are very protective of their children, so if they have any evidence against their children's boy/girlfriends, they will file a lawsuit. It is also a good way to make money for them too...I suppose. Also, one of the main reason is most teenage girls gets abortion, and parents don't really appreciate that. It does not matter if the minor individual who the adult had sex with enjoyed it or not, it is still considered as statutory rape. Most people define 'rape' as 'forcing someone to have sex with you'. There are other definitions of rape, depending on what type it is.