This particular tweet could be in response to former New York City mayor Rudy Giuliani, who recently appeared on an episode of ABC's This Week and postulated how Trump "has no intention of pardoning himself, but he probably does [have the power to]".
"It could lead to impeachment", Giuliani said, referring to the idea of Trump pardoning himself.
Among the subjects believed to be under investigation by Mueller's team are allegations of obstruction of justice against the president, a charge that the letter from Trump's legal team argues is invalid because the president, as head of the executive branch of government, has authority over all federal investigations.
White House press secretary Sarah Huckabee Sanders responded to a question about President Donald Trump's tweets Monday, suggesting members of the media should focus on concerns more important than the president's controversial tweets. Dowd, of course, exited the President's legal team only to be replaced by Giuliani.
For many months after Mueller's appointment a year ago, Trump avoided directly challenging the special counsel. Mueller is a registered Republican but Trump has nonetheless complained that his office is stacked with Democrats whose work amounts to a political "witch hunt".
"In this investigation, the crimes are really silly", said Giuliani, adding that firing Comey in 2017 can't possibly be an obstruction of justice, since Trump has the right to fire anyone, anytime, for any reason.
"The president is not saying he is going to pardon himself".
On Thursday, Trump stunned much of the political world by announcing a presidential pardon for the conservative commentator Dinesh D'Souza and floating the possibility of pardons for the television personality Martha Stewart and the former Gov. Rod Blagojevich of IL. "Let me remind you of something, we don't live in a monarchy and you are not a king".
"I'm not aware of an ask", she said, "but I would reiterate the president hasn't done anything wrong".
As special counsel Robert Mueller continues his probe into Russia's meddling in the 2016 presidential elections, he is said to be considering subpoenaing the president.
Trump hasn't been accused of wrongdoing, and highlighted that as he railed against Mueller's investigation.
Mr. Trump's legal team has long pushed the special counsel to narrow the scope of its interview.
Because the president's power is contained in the Constitution, it is part of the system.