FILE - In this Wednesday, Oct. 10, 2018 file photo, Mukhtar Robow, who was once deputy leader of Africa's deadliest Islamic extremist group the al-Qaida-linked al-Shabab, speaks at a press conference about his candidacy for a regional presidency, in Baidoa, Somalia. A Somali official says Ethiopian troops that are part of the African Union forces supporting the Somali government have arrested Robow in Baidoa. (AP Photo/File)

In this Nov. 29, 2018, file photo, Sen. Elizabeth Warren, D-Mass., speaks at the American University Washington College of Law in Washington, on her foreign policy vision for the country. Warren sought to solidify her connection with African-American voters Friday, Dec. 14, as she prepares to launch a potential presidential campaign. (AP Photo/Andrew Harnik, File)

FILE - In this Wednesday, Dec. 12, 2018 file photo, defendant Denise Williams listens during her trial for the murder of her husband Mike Williams, in Tallahassee, Fla. After a spellbinding five-day trial that featured tales of infidelity, a multimillion dollar insurance payout and family dysfunction, a jury on Friday, Dec. 14, convicted Williams of helping mastermind the killing of her husband nearly two decades ago. The 48-year-old Williams was found guilty after testimony by a key witness in the case, the man who shot her husband Mike Williams on a cold December morning on a large lake west of Tallahassee. (Alicia Devine/Tallahassee Democrat via AP, Pool, File)

FILE - In this Feb. 1, 2017, file photo, then - National Security Adviser Michael Flynn speaks during the daily news briefing at the White House, in Washington. Flynn is relaxed and hopeful even as the possibility of prison looms when he's sentenced in the Russia probe Tuesday, Dec. 18, 2018. The retired three-star general pleaded guilty last year to lying to the FBI about conversations he had with the then-Russian ambassador to the U.S. during President Donald Trump's White House transition. (AP Photo/Carolyn Kaster, File)

FILE - In this Aug. 1, 2017, file photo, Scott Blackmun, CEO of the U.S. Olympic Committee, speaks at Yongsan Garrison, a U.S. military base in Seoul, South Korea. Two lawmakers are asking the Justice Department and FBI to look into whether former U.S. Olympic Committee CEO Scott Blackmun lied to a Senate panel in testimony about the handling of sex-abuse allegations against Larry Nassar. At issue is Blackmun’s refuted claim that he discussed the case with USOC staff after receiving word of Nassar’s potential crimes from the USA Gymnastics president at the time, Steve Penny. (AP Photo/Lee Jin-man, File)

FILE - In this Oct. 23, 2018 photo, Borey Ai pauses outside of the Asian Americans Advancing Justice-Asian Law Caucus in San Francisco. Ai spent 19 years in prison before parole officials decided he'd turned his life around and he walked out of San Quentin and into the waiting arms of federal immigration agents. In a rare step, the California Supreme Court has blocked Gov. Jerry Brown's attempt to issue a pardon to a 37-year-old man Cambodian refugee facing deportation for killing and robbing a woman when he was 14 years old. The court offered no public explanation for its rejection on Wednesday, Dec. 5, 2018 of Borey Ai's pardon. (AP Photo/Jeff Chiu, File)

FILE - In this Jan. 20, 2017, file photo President Donald Trump, center, raises his fist alongside first lady Melania Trump, left, and son Donald Trump, Jr., after dancing at the Liberty Ball following his inauguration in Washington. Federal prosecutors are reportedly investigating the finances of Trump's inaugural committee and whether foreigners made illegal contributions to its events. (AP Photo/Patrick Semansky)

FILE - In this Jan. 8, 2009, file photo, ice fog envelops downtown Fairbanks, Alaska. Three Alaska groups on Friday, Dec. 14, 2018, sued the Environmental Protection Agency for a fourth time, claiming the agency has not enforced federal clean air law around Fairbanks, Alaska's second largest city. (Eric Engman/Fairbanks Daily News-Miner via AP, File)