GOP Doxxer- At the time of his arrest, Cosko was working as an unpaid intern for Rep. Sheila Jackson Lee, D-Texas, who fired him soon after. He was previously employed as a computer systems administrator in the office of Sen. Maggie Hassan, D-N.H., a job that gave him "intimate knowledge of, and broad access to" the computer systems in Hasan's office, according to court records. But he had been fired from Hassan’s office in May 2018 for failing to follow office procedures.
After the firing from Hassan's office, Cosko became angry and repeatedly burglarized the office without being detected, court records said. He copied gigabytes-worth of data, including dozens of user names and passwords belonging to Senate employees.