One of the more intriguing redactions that classification reviewers made to the sheaf of recently released commiques between the Justice Department and the Central Intelligence Agency is the codeword used to compartmentalize the existence of and information about the secret detention facilities and the enhanced interrogation techniques.
Now we're getting somewhere. The paralegal's job is to assist the U.S. Attorney with complex cases. I'm wagering a guess here that they involve terrorism and therefore include classified evidence obtained by the government's various intelligence collection programs. SI/TK/G/HCS stand for, in order, the compartments restricting access to info obtained from communication intelligence (eavesdropping), spy satellite, super-sensitive collection programs and from human sources -- HCS stands for HUMINT control system.