The U.S. EPA has given Sen. Barbara Boxer (D) only some documents related to the agency’s refusal to allow California to regulate car greenhouse-gas emissions — not all, as she had asked. Missing or redacted documents include a presentation said to predict that EPA would lose if sued over its recalcitrance (which, of course, it has been). Citing executive privilege, the EPA explained in a letter that it “is concerned about the chilling effect that would occur if agency employees believed their frank and honest opinions and analysis … were to be disclosed in a broad setting.” Hm, could that be because EPA staff reportedly unanimously opposed the agency’s final decision regarding California? The EPA also said that fully complying with Boxer’s request could “jeopardize the agency’s ability to effectively litigate claims related to California’s waiver request” and “result in needless public confusion.” Boxer called the agency’s failure to pass along the papers “an insult to the American people and a dereliction of duty.”