Updated

President-Elect Joe Biden has nominated Retired Army Gen. Lloyd Austin to serve in his administration as Defense Secretary, and some Democratic lawmakers will face a difficult decision when considering his candidacy.

Typically, in order for an individual to serve in the post he or she must be at least seven years removed from military service. Austin does not meet those requirements – he left the military in 2014 – which means lawmakers in the House and Senate would need to approve a waiver allowing him to serve.

Some Democrats were opposed to granting former Defense Secretary James Mattis who sought and received a waiver under President Trump.

Among those who voted against Mattis' waiver are Sens. Richard Blumenthal, D-Conn., Jon Tester, D-Mont., Chris Murphy, D-Conn., and Jack Reed, D-R.I.

Blumenthal and Tester have indicated they will not vote in favor of a waiver, leaving Murphy, Reed and some others in a difficult spot.

Prior to Mattis, the last time Congress granted a waiver for a Defense Secretary was in 1950 for George Marshall.

GOP SEN. COTTON TAKES AIM AT BIDEN'S DEFENSE SECRETARY NOMINEE

As previously reported by Fox News, a former CIA intelligence analyst who served in the war in Iraq three times under then-Presidents Barack Obama and George W. Bush, Rep. Elissa Slotkin, says that choosing retired four-star Gen. Lloyd Austin to lead the department “just feels off” since the seven-year rule is intended to ensure civilian oversight of the armed forces.

Slotkin's voice matters as a waiver must also be approved by the House. In 2016 the lower chamber passed the waiver request for Mattis by a vote of 268-151.

Austin served for more than four decades and, if confirmed, would be the first African American to lead the U.S. Defense Department.

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