Now the second question that anyone who is not American or Pakistani might ask who is Raymond Davis and what is the reason people are talking about him? If you want a brief overview of the case just look at this source.
Scenario: Raymond Davis, a US citizen, appointed as an Embassy Officer (not a "diplomat" as the documents from US or Pakistani Foreign offices fail to substantiate this claim so far), kills two individuals in the crowded area of famous city of Pakistan, Lahore. Why Raymond Davis killed these guys is, according to him an act of self defence. However, the Pakistani Police investigation reveals that it was not an act of self defence.
US Demand: Raymond is a diplomat and he enjoys immunity under Vienna Convention to be prosecuted in Pakistan. Immunity to kill ?
Pakistan Stance: Still waiting for the official stance of Pakistan's foreign office.
Where is Raymond Davis: Under custody of Pakistani police and also facing trials in Lahore High Court, Pakistan.
What is his Fault: Rather than performing his duties he was carrying unlicensed arms that tantamount to spying.
It is up to you people to decide what is the true justice.