Sens. Bob Menendez (D-N.J.), Mark Warner (D-Va.), and Sherrod Brown (D-Ohio) sent a letter to the inspectors general of the State Department, Treasury Department, and the intelligence community on Friday asking for an independent investigation into the Trump administration's failure to implement Russia sanctions passed by Congress last year.

"[I]t seems clear that several weeks ago the administration had identified specific Russian entities that had played a role in supplying or otherwise supporting the government of Syria's chemical weapons program, had prepared a list of such entities for sanctions designation, and Ambassador Nikki Haley publicly announced their imminent designation," the letter says, "but then did not designate them, reportedly at the direction of the president."

The White House has said the penalties imposed by the Countering America's Adversaries Through Sanctions Act (CAATSA) are unnecessary because the measure is already achieving its intended results. A State Department official said in January that the passage of CAATSA shows "significant transactions with listed Russian entities will result in sanctions. Sanctions on specific entities or individuals will not need to be imposed because the legislation is, in fact, serving as a deterrent."

The president has some executive discretion in enforcing the law, but its scope is the subject of legal debate. The senators' request is unlikely to be honored, The Washington Post reports, unless congressional Republicans support it as well. Bonnie Kristian

U.S. Customs and Border Protection has constructed just 1.7 miles of fencing along the southern border with the $1.57 billion Congress appropriated last year for the project, a lawyer for the House of Representatives told a federal judge on Tuesday.

In a court filing, attorney Douglas Letter told Judge Haywood Gilliam that this information is current as of April 30, Bloomberg reports. Letter also said this was three-quarters of a mile more than had been reported to Congress in February.

Gilliam is the judge in a lawsuit brought by 20 Democratic state attorneys general and the Sierra Club; they are trying to block Trump from using money from the Treasury and Defense departments to fund his border wall. Gilliam requested the information during a hearing on May 17. Catherine Garcia

The North American Aerospace Defense Command (NORAD) revealed on Tuesday that U.S. fighter jets intercepted six Russian warplanes off the coast of Alaska on Monday.

The four bombers and two fighter planes were intercepted by F-22 jets after they entered an area known as the Alaskan Air Defense Identification Zone, NBC News reports. In a statement, NORAD said the Russian planes "remained in international airspace and at no time did the aircraft enter United States or Canadian sovereign airspace," and the U.S. jets kept an eye on the Russian planes until they left the region.

Russia's Ministry of Defense said the planes were conducting planned exercises, which took place "over the neutral waters of the Chukotka, Bering, and Okhotsk Seas, as well as along the western coast of Alaska and the northern coast of the Aleutian Islands." Catherine Garcia

A confidential draft Internal Revenue Service memo directly contradicts Treasury Secretary Steven Mnuchin's reason for not turning over to Congress President Trump's tax returns, The Washington Post reports.

House Ways and Means Chairman Richard Neal (D-Mass.) formally requested Trump's tax returns last month; under a 1924 law, he is one of a handful of top lawmakers with the authority to do so. Mnuchin has refused to give Neal the returns, claiming Congress does not have a "legitimate legislative purpose" to request the documents.

The memo, obtained by the Post, states otherwise, asserting that it is "mandatory" the returns are disclosed, as the law "does not allow the Secretary to exercise discretion in disclosing the information provided the statutory conditions are met." The only way the IRS can refuse to comply with a Congressional subpoena "would be the invocation of the doctrine of executive privilege," the memo states, which has not happened.

The IRS told the Post the draft was prepared in the fall by a lawyer in the Office of Chief Counsel, and does not represent the "official position" of the agency. Trump has not released his tax returns on his own, first claiming that he can't do so because he is under audit, and later saying no one could understand his complex filings anyway. Catherine Garcia

A new CBS News poll finds that two-thirds of Americans do not want Roe v. Wade overturned, with 48 percent saying they would be angry if it were reversed.

The poll was conducted via telephone May 17 to 20, after Alabama passed the nation's strictest abortion law; the goal of anti-abortion lawmakers is to get a case to the Supreme Court so the justices can revisit Roe v. Wade. The poll shows that 26 percent of Americans would be satisfied if Roe v. Wade were overturned, while 23 percent don't think it would matter very much. Split by gender, 69 percent of women and 65 percent of men think Roe v. Wade should be kept as is, and 38 percent of women said they would be angry if it were overturned, compared to 24 percent of men.

Among Republicans, 45 percent say Roe v. Wade should be kept as is, while 48 percent want it overturned; 87 percent of Democrats say keep it as is, compared to 11 percent who want to see it overturned. Of the Republicans polled, 48 percent think abortion should be available but limited, while 16 percent think abortion should be generally available and 34 percent think it should be prohibited. On the Democratic side, 66 percent think abortion should be generally available, 20 percent think it should be available but limited, and 12 percent think it should not be permitted.

Pollsters spoke with a random sample of 1,101 adults nationwide. The margin of error is plus or minus four percentage points. Catherine Garcia

President Trump will nominate Barbara Barrett as Secretary of the Air Force, he announced on Tuesday.

"She will be an outstanding Secretary!" Trump tweeted. Barrett is the former chair of the Aerospace Corporation, and was the first civilian woman pilot to land an F-18 fighter jet on an aircraft carrier, The Arizona Republic reports. She is also a former ambassador to Finland and advised former Presidents George H.W. Bush and George W. Bush. In 1994, she became the first female Republican to run for governor in Arizona, but did not win the nomination.

Heather Wilson resigned as Secretary of the Air Force in March, in order to become the next president of the University of Texas at El Paso. Catherine Garcia

In public, Venezuelan opposition leader Juan Guaidó remains optimistic about his efforts to remove Venezuelan President Nicolás Maduro and his United Socialist Party from power. But, privately, The New York Times reports, Guaidó and his advisers are beginning to feel the pressure from Maduro's forces after the opposition's failed military uprising in April.

"The persecution has been savage," Guaidó, who is recognized by several countries, including the United States, as Venezuela's legitimate interim president, told the Times.

Nowadays, Guaidó is often stationed inside one of several safe houses, while his deputy chief of staff Rafael Del Rosario remains in exile, after escaping Venezuela with his family by foot, aided by soldiers sympathetic to Guaidó's cause. Several other soldiers and legislators who stood by Guaidó in April are reportedly either in jail or being harbored in foreign embassies.

The situation has the opposition seriously considering negotiating with Maduro, which Guaidó had previously rejected, the Times reports. Last week representatives from the opposition and Maduro's government traveled to Norway for preliminary talks, though Guaidó maintains that the goal is to remove Maduro. Even the United States, Guaidó's most fervent supporter, has taken a step back from the situation, as President Trump has turned his attention more heavily toward Iran in recent weeks, making it even more unlikely that the Venezuelan opposition could secure U.S. military support if the situation intensifies. Read more at The New York Times. Tim O'Donnell