Five Democratic senators today asked the Federal Bureau of Investigation (FBI) to find out who was behind attacks on the Federal Communications Commission's public commenting system. The FCC website failed on May 8 just as many people were trying to submit comments on the commission's plan to gut net neutrality rules.

"The public comment period associated with the FCC’s rulemaking authority is a critical part of the regulatory process and the primary way for the American people to make their voices heard," senators Brian Schatz (D-Hawaii), Al Franken (D-Minn.), Patrick Leahy (D-Vt.), Ed Markey (D-Mass.), and Ron Wyden (D-Ore.) wrote in a letter to FBI Acting Director Andrew McCabe. "The reported cyberattack on the FCC’s Electronic Comment Filing System is extremely troubling given that it threatens to stiﬂe the public’s ability to weigh in on these issues."

"We ask that the FBI prioritize this matter and investigate the source of this attack," the senators also wrote. "This particular attack may have denied the American people the opportunity to contribute to what is supposed to be a fair and transparent process, which in turn may call into question the integrity of the FCC‘s rulemaking proceedings."

Attacks and spam bots

The FCC initially attributed the downtime to "multiple distributed denial-of-service attacks (DDoS)" perpetrated by "external actors" who were trying to take down the website. Further analysis suggested that the incident was caused either by an unusual type of DDoS attack launched from a cloud service or poorly written spam bots.

Some net neutrality activists accused the FCC of inventing the attack, which apparently came just as a wave of net neutrality supporters tried to submit comments after comedian John Oliver tackled the subject in his HBO show. There are now more than 2.9 million comments on the FCC's net neutrality proposal, though many come from spam bots repeating the same comments over and over again.

Last week, people who say their names and addresses were attached to anti-net neutrality comments without their permission asked the FCC to notify other victims of the impersonation and remove fraudulent comments from the net neutrality docket. Today, a conservative watchdog group called the National Legal and Policy Center accused pro-net neutrality groups of spamming the comment system.

The FCC is accepting comments on its plan until August 16.

Wyden and Schatz previously asked FCC Chairman Ajit Pai for more detailed information on the DDoS attacks, and they requested a response by June 8. Today's letter to the FBI asks for an update on the status of the FBI's investigation by June 23. The FCC has said it spoke with law enforcement about the attack, but no details of any ongoing investigations have been revealed.

When contacted by Ars today, an FBI spokesperson said, "We received the letter and will provide a response to the members of Congress."