WATCH: Donald Trump signs his first official act as president, the waiver for retired Gen. James Mattis to serve as defense secretary. pic.twitter.com/MoL3m235cx — Washington Examiner (@dcexaminer) January 20, 2017

As one of his first actions as President, Donald Trump signed a waiver that will allow retired Marine General James Mattis to serve as Trump’s Defense Secretary. He still needs to be confirmed, but the waiver is a necessity because of a restriction under federal law that prevents Mattis from getting the position.

Federal law says that in order to serve as Secretary of Defense, a person has to be a civilian, and “may not be appointed as Secretary of Defense within seven years after relief from active duty.” Since Mattis only retired three years ago, he wouldn’t be qualified under the statute. The House approved the waiver on Friday in a vote of 268-151. Only 36 Democrats supported the bill. The Senate easily approved the waiver a day earlier. However, some Democrats opposed the bill fearing that it was too vague because it didn’t mention Mattis by name.

“If we don’t stand up for ourselves now, we’re going to be rolled over countlessly,” Rep. Adam Smith of Washington state, the ranking Democrat on the House Armed Services Committee said according to Politico.

The waiver for Gen. Mattis is just another example of Donald Trump thinking the rules that his predecessors followed shouldn’t apply to him. pic.twitter.com/S9NfpM49OK — Ruben Gallego (@RepRubenGallego) January 13, 2017

This isn’t the first time this has happened. General George C. Marshall became Secretary of Defense in 1950, despite having been Army Chief of Staff until 1945. Congress allowed Marshall to take the job, but they made it clear that they didn’t want to make a habit of doing this. When Congress passed legislation that let Marshall become Secretary, they specifically said, “the authority granted by this Act is not to be construed as approval by the Congress of continuing appointments of military men in the office of Secretary of Defense in the future.”

Ronn Blitzer contributed to this report.

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