It's not Facebook's job to keep false information off your timeline.

At least that's the perspective of Facebook CEO and founder Mark Zuckerberg, which he shared with shared with The Washington Post ahead of a speech at Georgetown University on Thursday. While Zuckerberg says he's worried about "the erosion of truth" in society, he's just not ready to root out falsehoods on his platform altogether.

Zuckerberg and Facebook have been criticized for letting false news stories and even false claims from politicians stand on the site. That issue was the focus of an experimental ad from Sen. Elizabeth Warren (D-Mass.), in which she claimed Zuckerberg endorsed President Trump for re-election just to see if the site would take it down. Facebook didn't, and on Thursday, Zuckerberg gave a reason why. "I don't think people want to live in a world where you can only say things that tech companies decide are 100 percent true," he said, adding that he fears "potentially cracking down too much" on free expression even if it can lead to confusion.

Still, Zuckerberg acknowledged that the power Facebook has on political systems is very much on his mind. He even considered banning political ads on Facebook altogether, he said Thursday at Georgetown. But that would result in a site that "favors incumbents and whoever the media covers," Zuckerberg added. Read more of Zuckerberg's political thoughts at The Washington Post. Kathryn Krawczyk

The number of reported cases of a pneumonia virus spreading through China jumped over the weekend, CNN reports, bringing the total to 201. On Friday, there were 62 reported cases of the illness in China. By Monday, another 139 cases had been reported, and three people had died. The virus, which originated in a wildlife market in the central Chinese city of Wuhan, has also spread to other countries, including South Korea, Thailand, and Japan, CNN reports.

Health authorities say the pathogen is a new strain of coronavirus, which CNN explains is "in the same family of the deadly severe acute respiratory syndrome (SARS)." Its symptoms include fever and shortness of breath, QZ reports.

The outbreak comes as China prepares to celebrate the Lunar New Year. Last year, CNN estimates 7 million people traveled outside the country for the occasion. South Korea has been screening travelers arriving from Wuhan for fever at Seoul's Incheon International Airport. Some airports in the U.S. are doing the same. However, CNN points out that "a new study by Imperial College London suggests the number of infections in Wuhan is likely to have been grossly underestimated."

"The detection of three cases outside China is worrying," Neil Ferguson, a disease outbreak scientist at Imperial College London, said. "We calculate, based on flight and population data, that there is only a 1 in 574 chance that a person infected in Wuhan would travel overseas before they sought medical care. This implies there might have been over 1,700 cases in Wuhan so far." Jessica Hullinger

Virginia officials braced for possible violence as buses packed with gun-rights advocates began arriving in the capital city of Richmond for a large Monday rally where authorities fear an outburst of violence by white supremacists, the Richmond Times-Dispatch reports. Gov. Ralph Northam (D) last week declared a state of emergency in Richmond, and temporarily barred people from carrying firearms on the grounds of the state capitol. Gun-rights advocates, who are planning a peaceful rally, challenged the ban in court, but lost. "Virginians have the right to assemble. And I believe in the right to bear arms. But what we have seen and heard in recent weeks has the potential to go far beyond these constitutionally protected rights," Northam said last week. "We are seeing threats of violence." Organizers said Monday's protests against possible new gun-control legislation could draw 50,000 people, the Richmond Times-Dispatch reports. Harold Maass

The Kansas City Chiefs beat the Tennessee Titans 35-24 to win the AFC Championship game on Sunday, earning the team its first spot in the Super Bowl in half a century, NPR noted. The Chiefs will play the San Francisco 49ers, who defeated the Green Bay Packers 37-20 in the NFC Championship game. The Chiefs came back from a 17-7 deficit in the first half. Kansas City was led by star quarterback Patrick Mahomes. He threw for three touchdowns and a total of 294 yards, including a 60-yard completion to wide receiver Sammy Watkins in the fourth quarter that helped seal the victory. "We're not done yet," Mahomes said. The 49ers earned their trip to professional football's Feb. 2 championship game with help from running back Raheem Mostert, who scored three touchdowns in the first half. Harold Maass

President Trump has a noon deadline on Monday to submit his written defense against impeachment charges before his Senate trial gets fully underway on Tuesday, Reuters reports. Trump, only the third U.S. president to face such a trial, refused to cooperate with the impeachment inquiry in the Democratic-controlled House, so the document will amount to his first comprehensive defense against the charges that he abused his power by pressuring Ukraine to investigate Democrats, and tried to obstruct the House investigation.

On Saturday, Trump's defense team called the impeachment process "a brazen and unlawful attempt to overturn the results of the 2016 election and interfere with the 2020 election." House Judiciary Committee Chairman Jerry Nadler (D-N.Y.) called the Trump legal team's response "errant nonsense," CBS News reports. Harold Maass

During the most recent Democratic presidential debate, Sen. Elizabeth Warren (D-Mass.) had a memorable zinger when the conversation inevitably turned to the question of her electability. "Can a woman beat Trump?" Warren asked. "Look at the men on this stage. Collectively, they have lost 10 elections. The only people on this stage who have won every single election that they have been in are the women. Amy [Klobuchar] and me."

It seems The New York Times took that to heart.

For the first time ever, the paper's editorial board endorsed not one but two presidential candidates on Sunday: Warren and, you guessed it, Minnesota Sen. Amy Klobuchar. In its announcement, the Times appeared torn, as many voters are, between "the radical and the realist models" on display within the Democratic field. But the paper said "Ms. Klobuchar and Ms. Warren right now are the Democrats best equipped to lead that debate."

While pushing back on more "radical" ideas of Warren's, "like nationalizing health insurance or decriminalizing the border," the paper's editorial board said her ideas "have matched the moment." It praised her anti-corruption legislation, along with her proposals on housing reform, energy policy, social security expansion, and childcare and education.

Meanwhile, the board called Klobuchar "a standard-bearer for the Democratic center" and applauded her long history as a lawmaker, noting she is "the most productive senator among the Democratic field in terms of bills passed with bipartisan support." The board was less enthusiastic about concerning reports about Klobuchar's management style. But otherwise it had very little criticism of her, aside from acknowledging "she has struggled to gain traction on the campaign trail."

The paper said its decision was likely to leave some readers "dissatisfied," and indeed, the blow back has already begun. You can read the entire endorsement — or rather, endorsements — at The New York Times. Jessica Hullinger

Former New York City Mayor Rudy Giuliani claims he'd "love" to be a witness in President Trump's Senate impeachment trial, reports The Hill.

Giuliani, who serves as Trump's personal lawyer, told radio talk show host John Catsimatidis: "I would love to see a trial. I'd love to be a witness — because I'm a potential witness in the trial — and explain to everyone the corruption that I found in Ukraine, that far out-surpasses any that I've ever seen before, involving Joe Biden and a lot of other Democrats."

Giuliani was allegedly involved in a push to pressure Ukraine into launching investigations into Trump's political rivals, working to dig up dirt on former Vice President Joe Biden and pushing out former Ukrainian Ambassador Marie Yovanovitch, who was reportedly viewed as an obstacle in obtaining the promise of investigations.

Democrats in Congress have called for the Senate impeachment trial, set to begin arguments this week, to include additional witnesses beyond those who testified in the House inquiry. Senate Republicans have so far declined the requests. No evidence has emerged to prove any wrongdoing by Democrats in Ukraine, but Giuliani said "I have those facts. I have those witnesses. I have documents, and I have recordings. And I would love to get them out in public." Summer Meza