Just days after he said he’s been appointed assistant secretary at the Department of Homeland Security, Milwaukee County Sheriff David Clarke has hit back against claims he plagiarized his 2013 master’s thesis. A report from CNN’s KFile late Saturday said Clarke’s thesis for his degree in security studies failed to attribute his sources at least 47 times. The report said Clarke directly lifted language from other sources and then failed to indicate in the thesis that the words were not his own with quotation marks, only indicating the sources in footnotes. In an email to The Milwaukee Journal Sentinel on Sunday, Clarke described the CNN report as part of a smear campaign, saying that “only someone with a political agenda would say this is plagiarism.” A spokesperson for the Milwaukee County Sheriff’s Department defended Clarke, saying he followed the school’s guidelines in writing the paper. The Naval Postgraduate School in Monterey, California, had already removed Clarke’s thesis from its website as of Saturday evening. The Department of Homeland Security has yet to confirm Clarke’s appointment, but he would not be the first one of Trump’s nominees to face plagiarism accusations. In mid-January, Monica Crowley, Trump’s nominee for the director of communications at the National Security Council, bowed out over claims she plagiarized portions of a 2012 book.