The WaPo reported (two weeks ago) that, after a US led airstrike in Azizabad reportedly killed 90 civilians (a claim the US is investigating, see NYT here), the Afghan government was reviewing its SOFA with the US. I have finally found an unofficial copy of the agreement between the US and Afghanistan on LEXIS. For those interested, the cite is 2002 U.S.T. LEXIS 100. The relevant paragraphs on immunity for US forces make relatively clear that US military personnel have immunity similar to Embassy administrative and technical staff. The agreement goes on to state that the US shall have authority to exercise criminal jurisdiction over “US personnel.”
While the agreement’s wording is not a model of clarity, I’ll excerpt the relevant portion for you below to draw your own conclusions about whether it grants the US authority to prosecute US military personnel, US civilian employees, and US government contractor personnel. The agreement uses the phrases US civilian personnel and contractor personnel elsewhere, so that may inform your interpretation of the term “US personnel.” Diplomatic Note No. 202:
The Government of Afghanistan recognizes the particular importance of disciplinary control by United States military authorities over United States personnel and, therefore, Afghanistan authorizes the United States Government to exercise criminal jurisdiction over United States personnel. The Government of Afghanistan and the Government of the United States of America confirm that such personnel may not be surrendered to, or otherwise transferred to, the custody of an international tribunal or any other entity or state without the express consent of the Government of the United States.