All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The texts of Quran and Sunnah indicate that it is forbidden for a person who is in a state of ihram (ritual consecration) for performing Hajj or ‘Umrah to kill game and underline that a penalty is due in case one does. Allaah Almighty says (what means): {O you who have believed, do not kill game while you are in the state of ihram. And whoever of you kills it intentionally – the penalty is an equivalent from sacrificial animals to what he killed…..} [Quran 5: 95]
Game, in this context, refers to eatable wild animals. But the penalty is not due in case of killing uneatable or domestic animals. When one forgetfully or mistakenly kills game, scholars unanimously agree that one is not guilty for that. They, however, provided different opinions on whether the penalty is due or not. The majority of the scholars are of the opinion that the penalty is due. In Al-Majmoo‘, An-Nawawi said:
According to our opinion (Shaafi‘i scholars), if a person in a state of ihram kills game intentionally, forgetfully or mistakenly, the penalty is due. This is also the opinion held by Abu Haneefah, Malik, Ahmad, as well as the majority of the scholars. Al-‘Abdari indicated that it is the opinion of all scholars of Fiqh.
Thus, the penalty is due when one kills game while he is in a state of ihram.
Allaah Knows best.