President Trump said that he would "first head to the U.S. Supreme Court" if congressional Democrats ever launched impeachment proceedings against him, writing on Twitter Wednesday that he "did nothing wrong."

"The Mueller Report, despite being written by Angry Democrats and Trump Haters, and with unlimited money behind it ($35,000,000), didn't lay a glove on me. I DID NOTHING WRONG. If the partisan Dems ever tried to Impeach, I would first head to the U.S. Supreme Court," Mr. Trump wrote in the first of two tweets.

The Mueller investigation reportedly cost around $25 million.

Get Breaking News Delivered to Your Inbox

Mr. Trump has repeatedly claimed that the report by Special Counsel Robert Mueller cleared him of any wrongdoing. But while it's true that Mueller could not establish that members the Trump campaign conspired with the Russian government to interfere in the 2016 election, it did not come to a conclusion as to whether the president obstructed justice.

Several congressional Democrats, including House Speaker Nancy Pelosi, have urged for caution when considering impeachment proceedings, arguing that House committees should continue their investigations before any decision on impeachment is made. Although some Democrats in Congress have called for Mr. Trump to be impeached, the majority of Democrats have remained silent on the issue.

Jonathan Turley, a law professor at George Washington University and a CBS News legal analyst, said that Mr. Trump may ask the Supreme Court to rule on the legality of impeachment because of the delay it would provide.

"While members are wrong to portray impeachment as a purely political process, the Supreme Court is unlikely to bar an impeachment process," said Turley, who was lead defense counsel during the last impeachment process for a U.S. district judge in 2010.

"Impeachment is based on a legal standard of 'high crimes and misdemeanors,' but the process and the merits were committed to the legislative branch by the framers. It is a standard that does not lend itself to judicial review or intervention," Turley said.