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Federal Communications Commission Chairman Ajit Pai was on the defensive Thursday when asked at a Senate oversight hearing why he didn't correct the record sooner about an alleged cyberattack on the FCC at the height of last year's net neutrality debate.

Pai defended his decision not to talk earlier about the findings of a report released last week by the FCC's Office of Inspector General, which determined there was no evidence such an attack occurred. The FCC chairman said he knew in January.

In a testy exchange between Pai and Democratic Sen. Brian Schatz from Hawaii, Pai said he'd had doubts but kept quiet because the IG's office asked him to while it referred the matter to the Department of Justice for a criminal investigation. (The Justice Department didn't find cause to investigate.)

"I made a judgment," Pai said. "Even though I knew I'd be falsely attacked."

The exchange came about a week after the IG report concluded the FCC's former chief information officer had misidentified the cause of a brief outage that hit the agency's online public comment system. The outage took place during the heated debate over repealing the popular 2015 net neutrality rules. Ex-CIO David Bray, who'd served in the same role under the Obama administration, called the outage a distributed denial-of-service (DDoS) attack. Such hacking attacks knock web pages offline by overwhelming them with data requests.

But the IG determined that what actually happened was the same thing that happened in 2014 when the public comment system failed during a previous debate over net neutrality. That outage, and last year's downtime, occurred just after comedian John Oliver urged net neutrality supporters watching his weekly HBO show to flood the agency with comments.

Still, despite skepticism among journalists, technology experts and even some members of Congress, Pai and his staff supported the CIO's assertion there'd been a DDoS attack.

"The tech community said that doesn't make any sense ... Sen. [Ron] Wyden and I said it didn't make sense ... You told Congress a federal crime was committed," Schatz said to Pai. "Why didn't you entertain any of those quite reasonable doubts that were out there?"

Pai shot back that his hands were tied.

"Once we knew the conclusion, it was hard to stay quiet," Pai said. He said he and his staff had to consider whether to ignore the IG's request for confidentiality and instead honor requests from Congress and the public for more information.

Schatz acknowledged that Pai was in a tough position, but he said he still couldn't "imagine there was not another way to deal" with Congress' oversight of the agency.

The comments were made as Pai and his fellow FCC commissioners testified before the Senate commerce committee, which oversees the agency. Though several issues were brought up at the hearing, including 5G wireless, rural broadband and robocalls, the repeal of net neutrality and the political divide between Democrats and Republicans stood out.

The Obama-era net neutrality rules prevented internet service providers from blocking or slowing access and prohibited carriers from charging internet companies a fee to access customers faster. The rules officially expired in June, but Democrats in Congress are trying to reinstate them through a Congressional Review Act resolution. The measure has already passed the Senate, but to take effect it must also pass the House by year's end and be signed into law by President Donald Trump.

In his opening remarks to the hearing, Pai said Democrats' fears that the repeal of the rules would kill the internet were overblown.

"It has now been 67 days since the repeal of the previous administration's utility-style internet regulations took effect," Pai said. "The internet is still open and free."

In his questioning, Sen. Ed Markey, a Democrat from Massachusetts who's led the Congressional Review Act effort in the Senate, pointed out that it's likely we haven't seen changes to the internet because there are a number of lawsuits underway challenging the FCC's repeal.

The lone Democrat on the FCC, Jessica Rosenworcel, concurred. She pointed to the fact that several states are pushing through legislation to create their own net neutrality rules and to the fact that governors in many states have also signed executive orders banning the states from doing business with companies that don't comply with net neutrality. That's a sign, she said, that these are popular protections Americans want in place.

Rosenworcel said that as of today ISPs have the legal right to block access to any website or service online. They also have the technology and the business incentive to do it. And she added it's only a matter of time before these companies exert this power over consumers.

"It's not good for anyone who consumes or creates content online," Rosenworcel said.

Net neutrality supporters say they aren't buying Pai's claims regarding the alleged cyberattack.

"Today Pai admitted he knew that the alleged cyberattack was bogus months ago," Sarah Roth-Gaudette, executive director of the grassroots group Fight for the Future, said in a statement. "No matter which side of the aisle you're on, you should be completely outraged."

As for Pai's remark that the sky hasn't fallen since the net neutrality repeal, Roth-Gaudette called it "bogus and naive."

"With a vote to overturn the repeal passed in the Senate and pending in the House, and 23 attorneys general suing the FCC over it, Internet service providers like Comcast and AT&T aren't going to restructure the entire Internet while the heat is on," Roth-Gaudette said. "The FCC's net neutrality repeal is not only undemocratic, it's illegitimate. And Congress must reverse it by passing the CRA as soon as possible."

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