Fifteen year old committed Zina
10-4-2001 | IslamWeb
Question:
A 15 years-old girl committed adultery (Zina) with her 24 years old boyfriend. Because the girl is still below age (according to our law), her boyfriend was charge for rape and sentence for several years in jail .What was Islamic view about this matter.
Answer:
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad 
is His slave and Messenger.
If the mentioned girl committed fornication (Zina) willingly, she is considered a fornicator provided she is mature (i.e. reached the age of puberty).
If she was actually compelled to commit this sin, then she is not responsible for that sin. But she is obliged to protect herself by being far from places where she could be raped. It is also an obligation on her guardians to protect her from practicing unlawful acts, which could cause harm to her.
The ruling of Islam concerning the one who involves in illegal sex is as follows:
If the free person who indulged in illegal sex is married then he/she should be stoned till death. There is no difference between the man and the woman in this ruling. There is a consensus of the companions of the Prophet and other Muslim scholars upon this ruling as Ibn Qudamah mentioned in his book, Al-Mughni. If the free person who practiced illegal sex is unmarried then he/she should be flogged hundred stripes.
The slaves would be flogged only fifty stripes regardless of their being married or not.
Allah Says (what means): {But once they are sheltered in marriage, if they should commit adultery, then for them is half the punishment for free [unmarried] women.} [Quran 4:25]
The Shaafi’i and Hanbali Schools of jurisprudence held the opinion that a free unmarried person, whether a male or female, should be exiled from the place where he/she committed Zina for one year. The Maaliki School are of the view that the ruling of expulsion applies only to males, not females. Probably the first opinion is the most preponderant for the Hadeeth in which the Prophet said: “Receive (teaching) from me, receive (teaching) from me. Allah has ordained a way for those (women). When an unmarried male commits adultery with an unmarried female (they should receive) one hundred lashes and exiled for one year. And in case of married male committing adultery with a married female, they shall receive one hundred lashes and be stoned to death.” [Muslim]
The Prophet did not differentiate between a male and female in this ruling of expulsion.
Allah knows best.