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‘Angry’ Ex-Dem Staffer Who Doxed GOP Senators During Brett Kavanaugh Hearings Is Going to Prison


A 27-year-old former Democratic staffer for Sen. Maggie Hassan (D-N.H.) who later interned for Rep. Sheila Jackson Lee (D-Texas) was sentenced on Wednesday to 48 months in prison for doxing Republican U.S. Senators during the Brett Kavanaugh Supreme Court confirmation hearings of 2018, and more.

U.S. District Judge Thomas Hogan said that “We have … a society that has become very vicious,” adding that it was “very concerning to the court and unfortunate” that Jackson Cosko “played into that.”

The judge sentenced Cosko to 48 months, “followed by Thirty-Six (36) Months of Supervised Release on each count to run concurrent with each other and a Special Assessment of $100.00 on each count for a total of $500.00.” Cosko pleaded guilty in April to two counts of making public restricted personal Information, one count of computer fraud, one count of witness tampering and one count of obstruction of justice.

The sentencing memo filed on June 11, which you can read in full below, tells the story.

The defendant has pleaded guilty to carrying out a months-long series of burglaries and sophisticated data theft offenses directed at the office of United States Senator Maggie Hassan; to a separate set of “doxxing” offenses through which he maliciously released personal information of Senators Lindsay Graham, Orrin Hatch, Mike Lee, Rand Paul, and Mitch McConnell; and to obstruction of justice, because he attempted to silence a witness by threatening to release the private health information of a Senator’s children, because he corrupted another person and persuaded her to attempt to “wipe down” the scene of his burglaries, and because he attempted to destroy evidence in his own apartment. The defendant ultimately pleaded guilty to five felony counts.

Prosecutors, who recommended 57 months in prison, said that Cosko’s crimes “spanned several months and reflected a deliberate malice and self-righteous entitlement that distinguishes his offense conduct from purely impulsive, one-time mistakes, and from offenses driven solely by intoxication or addition.”

The government said that Cosko “essentially decided that his targets deserved it.”

Other implications:

The defendant’s doxxing conduct also prompted unidentified third parties to direct retaliatory abuse and racial harassment at another staffer in the House of Representatives – someone who was entirely innocent, but because the defendant used a shared IP address to conduct his doxxing, and because he hid his true identity (leading to speculation about the identity of the perpetrator), third parties wrongly blamed the other staffer for the defendant’s conduct. They then subjected her to voluminous online harassment, causing her to temporarily leave her house for safety reasons – the very same type of harm that the defendant inflicted on his own targets.

Furthermore, another ex-Hassan staffer, Samantha Deforest-Davis, has been charged in connection with this case for evidence tampering and for aiding and abetting computer fraud. According to The Hill, Davis is expected to plead guilty to misdemeanors.

Prosecutors described Cosko as “angry” on a couple of occasions.

The government said that after Cosko was fired from Hassan’s office in May 2018 for “performance-related reasons,” an “indignant” Cosko was driven by “anger” to launch an “extensive computer fraud and data theft scheme that he carried out by repeatedly burglarizing Senator Hassan’s Office.”

“The defendant ultimately copied entire network drives, sorted and organized sensitive data, and explored ways to use that data to his benefit,” the government said.

Here was a prime example of Cosko’s clandestine operation:

During his repeated burglaries of Senator Hassan’s Office, and assisted by the insider knowledge that he gained as a system administrator in that Office, the defendant obtained and took dozens of means of identification (including network login credentials) belonging to at least six employees of the Office of Senator Hassan – that is, his conduct constituted numerous instances of identity theft. The defendant also surreptitiously installed “keylogger” devices on at least six computers in Senator Hassan’s Office. The keylogger devices were designed to be unobtrusive, legitimate looking devices that would go unnoticed by the individuals that were using the affected computers. They were also designed to record the keystrokes that Senate staffers typed on their Senate-owned computers – including the keystrokes that comprised usernames and passwords for Senate computers and computer networks, as well as personal e-mail accounts.

The Kavanaugh Hearings

Prosecutors again said that Cosko “became angry” on September 27, 2018, while watching the Kavanaugh hearings on TV, an ended up “maliciously publishing the personal home addresses and telephone numbers of Senators Lindsay Graham, Orrin Hatch, and Mike Lee.”

Cosko’s intention, the government said, was to “intimidate the Senators, and with the knowledge and intent that others who learned of the information would then use the information to intimidate the three aforementioned Senators, as well as members of their immediate families, by using the information that the defendant had now made public.”

Cosko proceeded to edit WikiPedia articles “so that the articles would include the Senators’ home addresses and telephone numbers.”

“The defendant also helped publicize those edits, by posting or ‘re-tweeting’ posts about his edits over Twitter,” prosecutors said.

When Sen. Rand Paul (R-Ky.) called for investigation into the doxing, Cosko decided to publish the “personal home addresses and telephone numbers of Senator Paul as well as Senate Majority Leader Mitch McConnell, with the intent to intimidate them, and with the knowledge and intent that others would use that information to intimidate them.”

When Cosko edited Paul’s WikiPedia article on Oct. 1, 2018, he included the phrases “He dares call for an investigation of ME?!?!?!? . . . I am the Golden God! … Also It’s my legal right as an American to post his info … We are malicious and hostile . . . Send us bitcoins . . . Wednesday night will be the doxxed next[.]”

“Witness 4” in the case would tell prosecutors that Cosko believed the effects of his doxxing were “really funny.”

The government concluded that there were “no particularly mitigating circumstances.”

The defendant appears to be an intelligent and capable adult, having been raised by a good family in a stable environment, having graduated from college and pursued a graduate degree, and having enjoyed significant and loving support from both parents. While the defendant does have a criminal history, and a history with illegal drug use, a review of the PSR shows that there are no particularly mitigating circumstances in the defendant’s character or background.

Cosko worked for Rep. Sheila Jackson Lee as an unpaid intern for 38 days until he was arrested. The representative said she was “entirely unaware” of Cosko’s “indefensible and criminal behavior.”

Jackson Cosko sentencing memo by Law&Crime on Scribd

Editor’s note: this article previously identified Sheila Jackson Lee, erroneously, as a Senator. 

[Image via Win McNamee/Getty Images]

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Matt Naham is the Senior A.M. Editor of Law&Crime.