From the president, on Twitter:
"I will be asking for a major investigation into VOTER FRAUD, including those registered to vote in two states, those who are illegal and... even, those registered to vote who are dead (and many for a long time). Depending on results, we will strengthen up voting procedures!"
Why it matters: The White House has been claiming, with no evidence, that 3 to 5 million people voted illegally in November. Such an investigation would be undertaken by the Department of Justice, whose nominee (Jeff Sessions) has yet to be confirmed.