Everyone wants a cure for COVID-19, the new coronavirus spreading around the world and causing economic and social upheaval. An effective treatment would also go a long way toward helping the world amble toward normalcy while researchers develop and test a vaccine. President Trump has put great store in hydroxychloroquine, a malaria drug used now to treat lupus and rheumatoid arthritis, but his federal health and medical advisers are skeptical.

The idea of the drug as a potential COVID-19 treatment started with Chinese reports of clinical trials, a tweet from Nigeria, and Facebook posts from France, Washington Post fact-checker Elyse Samuels recounts, but it started taking off in the U.S. when a block-chain investor tweeted a Google Doc he co-wrote exploring chloroquine's coronavirus-slaying properties — and Elon Musk retweeted it three days later, on March 16. Conservative media picked up the claims, then Fox News, and finally Trump and his close allies.

"As hype around the drugs continued, experts were wary about a lack of scientific evidence," with Dr. Anthony Fauci repeatedly noting there was nothing but "anecdotal reports" backing up the drug's claims, Samuels noted, explaining: "Anecdotal evidence is like a Yelp review, but for science." Trump argues that coronavirus patients have nothing to lose, but "there have been and will continue to be negative consequences of overpromising the drug's potential," she added. "Rumors on the internet are the least reliable source of information, and politicians are not qualified to give scientific advice, despite even the best of intentions." Watch Samuels' brief history of a would-be miracle cure, and her conversations with experts on why it probably isn't, below. Peter Weber

Rudy Giuliani has been hard at work crafting the defense for President Trump's upcoming Senate impeachment trial. But on Sunday, he told ABC News that he could no longer represent Trump in the trial because of his own involvement in said trial.

The House last week impeached Trump for a second time, charging him for "incitement of insurrection" after his supporters launched a deadly riot at the U.S. Capitol on Jan. 6. Before the riot, Trump gave a rally speech in which he repeated unfounded claims of mass voter fraud in the 2020 election, called the election outcome an "assault on our democracy," and urged supporters to "walk down to the Capitol." Giuliani spoke before Trump took the stage, and called for "trial by combat" against the Democrats.

Before abandoning the case, Giuliani told ABC News that his plan was to essentially argue that the president's voter fraud claims were true, prompting some eyebrow raising from Republican strategist Karl Rove:

It's not clear who will represent Trump in the trial now, as "many of the lawyers involved in the president's first impeachment, including White House counsel Pat Cipollone and his deputies and outside lawyers Jay Sekulow and Jane and Marty Raskin, do not plan to return for the second trial," ABC reports. Giuliani was one of Trump's last remaining "steadfast defenders," The Washington Post says, but Trump recently refused to pay Giuliani's $20,000-per-day legal fees. Jessica Hullinger

President Trump plans to spend his final days in office issuing about 100 pardons and commutations, according to CNN. It's not clear yet who will get a pardon, but "the expectation among allies is that Trump will issue pardons that he could benefit from post presidency," CNN reports. The final list apparently includes "white collar criminals, high-profile rappers, and others but — as of now — is not expected to include Trump himself."

One name expected to be on Trump's clemency list is Dr. Salomon Melgen, an eye doctor in Palm Beach, Florida, sentenced to 17 years in prison for health-care fraud. CNN reports some Trump allies were surprised to see Melgen's name on the list, but notes that "Melgen is seen as a wealthy and influential figure in south Florida," where Trump apparently plans to live after leaving Washington.

"Everything is a transaction," one source told CNN. "He likes pardons because it is unilateral. And he likes doing favors for people he thinks will owe him."

About 14,000 people have filed petitions for clemency from Trump, according to The Washington Post, and he has been "besieged" by lawyers from wealthy clients who are seeking a clean slate, as well as advocates for criminal justice reform who say their clients were wrongfully convicted.

Trump has granted clemency to 94 people throughout his presidency, most of whom were "friends and political allies," including his former campaign chair Paul Manafort, his confidant Roger Stone, and Charles Kushner, the father of Trump's son-in-law Jared Kushner. Jessica Hullinger

Communities around the nation are holding scaled down events to mark Martin Luther King Jr. Day on Monday. Marches, parades, and other events that normally draw crowds honoring the slain civil rights leader were canceled due to the coronavirus pandemic, which has hit Black Americans particularly hard. The National Civil Rights Museum in Memphis, Tennessee, normally hosts up to 12,000 visitors on the day, offering activities for families, but this year it is marking the holiday online.

The altered celebrations follow months of Black Lives Matter civil rights protests after the deaths of George Floyd and Breonna Taylor at the hands of police, and the attack on the U.S. Capitol Jan. 6 by a mob of Trump supporters that included white nationalists.

The New York Times has a nice list of ways to celebrate the national holiday safely here. Harold Maass

Parler, the social media site popular with conservatives fleeing Facebook and Twitter, came back online Sunday after finding a new hosting platform, CNN reports. "Hello world, is this thing on?" Parler CEO John Matze said in a message dated Saturday, Jan. 16. Parler had been down since Jan. 10 after getting the boot from Amazon Web Services in the aftermath of the deadly storming of the Capitol by Trump supporters. AWS said it had spotted dozens of threats of violence on Parler that violated its terms of service. Parler responded with a lawsuit against Amazon, asking a federal court to block Amazon's decision.

While Parler's site was back online, its app remained unavailable for download after being booted from the Apple and Google app stores. Harold Maass

President-elect Joe Biden's incoming White House chief of staff, Ron Klain, predicted on Sunday that the coronavirus death toll would reach 500,000 in the first weeks of the new administration. The current toll is 397,600, and it is expected to exceed 400,000 by Biden's inauguration on Wednesday. "The virus is going to get worse before it gets better," Klain said on CNN's State of the Union. "People who are contracting the virus today will start to get sick next month, will add to the death toll in late February, even March, so it's going to take a while to turn this around."

Biden has vowed to step up the pace of vaccinations, aiming for 100 million inoculations within 100 days. Dr. Anthony Fauci, a leading infectious-disease authority on the federal coronavirus task force, said on NBC News' Meet the Press that Biden's goal "is absolutely a doable thing." Harold Maass

Some 25,000 National Guard troops are being dispatched to Washington, D.C., this week ahead of President-elect Joe Biden's inauguration ceremony Wednesday, and the Federal Bureau of Investigation plans to subject all of them to additional vetting amid concerns of an "insider attack," The Associated Press reports.

Law enforcement agencies routinely scrutinize service members to root out those with any potential links to extremist views. But as AP reports, this practice has for years focused on "homegrown insurgents radicalized by al-Qaida, the Islamic State group, or similar groups." In this case, though, the FBI is worried about troops who might harbor animus toward the incoming administration "fueled by supporters of President Donald Trump, far-right militants, white supremacists, and other radical groups."

Trump has been widely blamed for inciting the violent insurrection attempt on the U.S. Capitol earlier this month, which left five people dead. Ongoing threats of violence have led to increased security in Washington — where the National Mall will be closed for Inauguration Day — and around the country.

Military and law enforcement personnel have been running drills in preparation for Inauguration Day, studying maps of the D.C. area, and plotting their routes. The FBI vetting process for National Guard members will likely involve scanning databases and watch lists for red flags, AP reports. Troops are also being trained on how to spot threats within their ranks.

"The question is, is that all of them? Are there others?" asked Army Secretary McCarthy. Read more at AP. Jessica Hullinger