William McGinley is returning to the Trump White House to serve as his White House Counsel, President-elect Trump announced.

"I am pleased to announce that William Joseph McGinley will serve as my White House Counsel," the appointment announcement noted.

In the announcement on Tuesday evening, Trump said McGinley played a "major role" in his election victory as the Republican National Committee’s outside counsel for election integrity.

"Bill is a smart and tenacious lawyer who will help me advance our America First agenda while fighting or election integrity and against the weaponization of law enforcement," the announcement said.

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The White House Counsel typically plays a key behind-the-scenes role in vetting Supreme Court candidates and nominees.

Having already picked three Supreme Court justices in his first term, Trump will have appointed a majority of the court if he lands two more in his second term.

McGinley served in the first administration for Trump as the White House Cabinet secretary as well as serving as General Counsel at the National Republican Senatorial Committee. 

Prior to his political appointments, he was a partner at two international law firms.

The selection marks another addition to Trump’s quickly forming Cabinet.

Trump has selected top Republicans, with the president-elect expected to select Florida Sen. Marco Rubio to serve as his Secretary of State and South Dakota Gov. Kristi Noem as secretary of Homeland Security. 

In addition, Rep. Elise Stefanik, R-N.Y., has been tapped for United Nations ambassador and former Arkansas Gov. Mike Huckabee as ambassador to Israel.

Fox News' William Mears Jr. contributed to this report.