If these conventions apply then the Pakistani justice officials spurred on by people in the streets insist they will determine whether or not Davis is/was a true diplomat (or something else)
Earlier the question has been raised among Pakistani leaders: "What diplomat would carry a revolver?" (Indeed, is this the rule among US diplomats or no?)
Meantime, sounds like the Pakistani court and prime minister, Gilani, are holding firm that the Pakistani court will try Davis soon and Kerry is needing to wait.
For items related to this case as well as the conventions, see The International News of Pakistan. I have also posted a few :) articles on this case below and at nomorecrusdes. (where at the very end of the article UPDATED...on Raymond Davis for February 7, 2011 - the reader will find a compact description (by an expert of law) covering what is entailed (and who is entitled) by the international laws covering diplomats.
US weblogs on firedoglake have also been carrying some Op Ed on this case.
I wonder why US Senator Kerry doesn't take the offer to release Aafia Siddiqui in exchange for Raymond Davis? This could spare Davis death by hanging and help ease the deep rift and palpably growing tension between the two nations.