So apparently it's official. Raymond Davis is a CIA contractor, employed by XE Services (formerly Blackwater). This is pretty much the most inflammatory information that could have been released in this increasingly heated case. That said, it is perhaps wise of the US to confirm the accusation now, rather than flatly deny it and raise the fallout later down the line. I heard a report over WTOP today about this case, and one of the major issues in this case is Davis' physical protection. According to the report, Davis has a private area in the prison he is being held in, and his guards are forbidden to carry guns. Dogs test his food for poison at each meal. This treatment is because of the explicit threat of death from angry Pakistanis. President Obama is at this juncture calling for Davis' release, so that he can be brought back to the US. If this happens, it will undoubtedly be one more bit of tarnish on the strained relationship between the US and Pakistan, if Davis' actions have not already given enough fuel to the fire.
Of course, the US can not allow one of its citizens to be a victim of vigilante justice, especially in a foreign country. The Pakistani government, for what it's worth, must understand this, or else they wouldn't be making such a large show of calling for a fair criminal trial. As CNN predicts it, at stake for Pakistan is the billions of dollars in aid and military funding that the US provides annually.
I think that the best outcome for the US will entail presenting a fair face to the global community. While it is likely impossible to have any strong persuasive impact on the Pakistani people at this point, saving face with other countries is a respectable goal. The same holds true for the Pakistani government. If they can avoid a vigilante killing from more traditional sources, then they will appear stronger in the eyes of other governments, and could conceivably come off as a more credible entity to the American public.