The Environmental Protection Agency's inspector general is opening an investigation into Administrator Scott Pruitt's use of multiple email accounts.
Inspector General Arthur Elkins said in a letter released Tuesday that his office will review the matter, the latest in a series of federal investigations of Pruitt's travel, security and spending and other issues.
The request for the email investigation came from Democratic Sens. Tom Carper of Delaware and Jeffrey Merkley of Oregon. Carper released a copy of the IG's response.
The senators asked the IG to review whether Pruitt was complying with federal law and EPA policy when using multiple email accounts and whether all accounts are searched when responding to Freedom of Information Act requests.
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EPA spokesman Jahan Wilcox said Tuesday that the agency does not comment on matters before the inspector general. He referred to a previous statement that EPA has three emails accounts for Pruitt, two used by staff for maintaining his calendar and public correspondence and the third for Pruitt himself.
"When we receive a FOIA request all accounts are searched before we respond to the FOIA request," he said.
A House committee and the Government Accountability Office also are conducting investigations and audits related to Pruitt's actions as EPA chief.
Last month, the Republican chairman of a Senate oversight committee, Sen. John Barrasso of Wyoming, issued a letter asking Pruitt to disclose all his email addresses and affirm that all were being searched in response to Freedom of Information Act requests.