This explains why Pakastan hasn't executed the killers of Richard Pearl.
Full Quote: (so no one can claim it is out of context)
Sahih Bukhari
Volume 9, Book 83, Number 50:
Narrated Abu Juhaifa:
I asked 'Ali "Do you have anything Divine literature besides what is in the Qur'an?" Or, as Uyaina once said, "Apart from what the people have?" 'Ali said, "By Him Who made the grain split (germinate) and created the soul, we have nothing except what is in the Quran and the ability (gift) of understanding Allah's Book which He may endow a man, with and what is written in this sheet of paper." I asked, "What is on this paper?" He replied, "The legal regulations of Diya (Blood-money) and the (ransom for) releasing of the captives, and the judgment that no Muslim should be killed in Qisas (equality in punishment) for killing a Kafir (disbeliever)."
Reference Tools:
http://etext.virginia.edu/koran.html
http://www.usc.edu/dept/MSA/reference/searchhadith.html
http://www.muslimhope.com/SourceMaterials.htm