Capitol Hill Staffer Accused of Doxxing Several Republican Senators

October 4, 2018 Updated: October 4, 2018

A man who had worked as a congressional staff intern for a number of Democrats has been arrested for allegedly doxxing—collecting someone’s personal and private information and releasing that on the internet—”one or more” Republican senators.

Jackson Cosko, 27, of Washington faces multiple charges, including making public restricted personal information, witness tampering, threats in interstate communications, unauthorized access of a government computer, identity theft, and more, U.S. Capitol Police said.

Capitol police said Cosko was arrested on Oct. 3, adding that an “investigation will continue and additional charges may be forthcoming.”

According to reports, during last week’s Senate Judiciary Committee hearing with testimony from Supreme Court nominee Brett Kavanaugh and one of his accusers, Christine Blasey Ford, the personal information of Sens. Mike Lee (R-Utah), Lindsey Graham (R-S.C.), Orrin Hatch (R-Utah), Rand Paul (R-Ky.), and Mitch McConnell (R-Ky.) was added to their public Wikipedia pages. The Wikipedia entries were allegedly edited to show the senators’ home addresses, phone numbers, and email addresses.

Most recently, Cosko was interning for Rep. Sheila Jackson Lee (D-Texas), a member of the House Judiciary Committee, according to a September letter that identified him. Lee’s chief of staff, Glenn Rushing, said Cosko was fired after the news surfaced; Lee’s office is cooperating with law enforcement.

Previously, Cosko also worked with Sen. Maggie Hassan (D-N.H.), former Sen. Barbara Boxer (D-Calif.), and with the office of Sen. Dianne Feinstein (D-Calif.), the ranking member of the Senate Judiciary Committee, according to Fox News. He also worked with a least one other unidentified lawmaker.

Cosko describes himself as a “Democratic Political Professional & Cybersecurity Graduate Student” on his Linkedin account. He graduated from The George Washington University in 2o14.

Sen. Paul had earlier called for an investigation into the breach.

“Yesterday, there was an attempt to incite people by publishing the personal information of Senators—including home addresses—endangering them & their families,” Paul wrote in a Sept. 28 Twitter post. “This should be investigated & the perpetrators punished. There is too much hatred and violence in politics these days.”

The doxxing was first discovered by a Twitter bot that tracks Wikipedia page edits. It also found that the changes were made from a computer in the House of Representatives.

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