There should be some regulation of Facebook, Rep. John Sarbanes told CNBC on Tuesday.
"They have a tremendous amount of power," the Democratic congressman from Maryland said on "Power Lunch."
"With that power comes responsibility to protect the privacy of people's data."
In his testimony, Zuckerberg said Facebook didn't notify the Federal Trade Commission about the Cambridge Analytica data leak years ago because the social media giant "considered it a closed case."
In addition, he said, combating election interference is one of his "top priorities" this year.
Sarbanes, a member of the House Energy and Commerce Committee, will also get a chance to question Zuckerberg when the CEO appears before that committee on Wednesday.
Facebook is under scrutiny after reports that research firm Cambridge Analytica improperly gained access to the personal information of as many as 87 million Facebook users. The company also has faced questions after reports of Russian meddling during the 2016 presidential election.
The House Energy and Commerce Committee released Zuckerberg's prepared remarks on Monday.
In those remarks, he says, "It's clear now that we didn't do enough to prevent these tools from being used for harm as well. That goes for fake news, foreign interference in elections, and hate speech, as well as developers and data privacy. We didn't take a broad enough view of our responsibility, and that was a big mistake. It was my mistake, and I'm sorry. I started Facebook, I run it, and I'm responsible for what happens here."
Rep. Bill Johnson, R-Ohio, hasn't made up his mind yet on whether Facebook should be regulated, telling "Power Lunch" he's "keeping an open mind."
"There is no question in my mind that Facebook is an American success story," said Johnson, also a member of the House Energy and Commerce Committee. "It has enhanced the way that Americans communicate and connect with their loved ones, with their friends. But there are very serious concerns here."
His main concern is whether Facebook is a content provider and if so, how it goes about setting the rules for what kind of content is displayed and who makes those decisions.
"Privacy and truth and fairness is what this is all about," Johnson said.
Sarbanes, meanwhile, is more focused on the data issue.
Facebook is not just a "harmless hangout" for your friends, he said. "It's one of the largest data brokerage firms in the world, vacuuming up data on 2 billion people every single day. It's a political ad platform and it's a communication company in many respects."
He wants to make sure that data isn't compromised and wants to ensure the company isn't being taken advantage of by advertisers, particularly political advertisers and foreign interests.
— CNBC's Sara Salinas contributed to this report.