The Environmental Protection Agency said Friday that Scott Pruitt, the administrator, spent $3.5 million on security over the last year, which Senate Democrats are running with as proof that Pruitt’s defense for the spending is an attempt to “muddy the waters.”

“Mr. Pruitt wants to muddy the waters after racking up massive travel bills, but he’s not fooling anyone,” said Democrats in a joint statement led by Sen. Tom Carper of Delaware, the top Democrat on the Environment and Public Works Committee. “Parents and families across the country are watching his administration brazenly misuse their tax dollars — dollars they expect will be spent protecting their children and communities from toxic chemicals and pollution, not on premium travel for him, his staff and his private security entourage.”