Can Democrats put a path to citizenship for dreamers in a budget bill? Can they provide universal prekindergarten? Paid family leave?

Answering those questions is the job of little-known staffer in the Senate, the parliamentarian. And her reading of Senate rules is having major policy implications for Democrats’ $3.5 trillion spending bill. Here’s who she is and what role she will play in the reconciliation process.

What is a Senate parliamentarian?

It’s the nonpartisan rule keeper of the Senate. “She’s essentially an umpire,” said Donald Ritchie, a former Senate historian. “She doesn’t write the rules, she enforces them.”

This is not an easy job, even in less partisan times. The Senate rules are old — like 18th century old. In addition, senators have layered on centuries of precedent that sometimes contradict the rules. There’s actually a big, thick book of precedents in the Senate. It’s the parliamentarian’s job to untangle all this and advise senators in a nonpartisan way during legislative battles on what they can and can’t do.

Ritchie said that for the first century or so, the vice president, in his role as the president of the Senate, was the parliamentarian. But in the 1930s, there was a Senate clerk who knew the rules so well that the vice president decided to make him the official rules keeper.

The Senate can fire parliamentarians, but they can’t pick their own people to serve in the role. There’s a parliamentarian office, where people work and study for years and years to get to the job. That creates a line of succession that insulates the job from politics.

Naturally, parliamentarians upset half the Senate while pleasing the other half. One parliamentarian, Bob Dove, got fired by Democrats in the ’80s, rehired by Republicans in the ’90s, and fired by Republicans in the 2000s.

Who is the parliamentarian?

Elizabeth MacDonough. She’s been in the job for a decade. Ritchie said she’s whip smart and very funny; on tours, she likes to call the rules of the Senate “so much powdered wiggery” in reference to how old they are.

When Republicans were trying to pass their 2017 tax law under reconciliation, she ruled against a few small provisions, including the name of the bill, the “Tax Cuts and Jobs Act.”

Earlier this year, she ruled that Democrats can’t legislate a $15 minimum wage into their coronavirus relief package.

In the Jan. 6 insurrection, she and her team rescued the electoral ballots as senators were rushed out of the chamber.

Now, she’s making big rulings on whether Democrats can include immigration in a major legislative package they’re trying to push through without Republican votes.

Why MacDonough matters

Democrats are trying to use a process called reconciliation to pass a $3.5 trillion spending bill that they want to squeeze major policies into. This is a budget tool that’s not meant to be used for major policy legislation. But it’s increasingly getting used that way by both parties, because it allows them to pass legislation with 51 votes rather than the 60 votes required to pass legislation over a filibuster.

The rules of reconciliation are specific. It can only be used to pass legislation related to spending and revenue, and it can’t add to the national deficit after the first decade.

Democrats are trying to stuff a lot into that narrow definition. While the Senate is still working on completing its bill, we know from House Democrats’ version of the same legislation that it will likely try to expand the child tax credit, create universal prekindergarten, expand family leave, expand Medicare, outfit buildings to be more environmentally friendly and perhaps even create a path to citizenship for dreamers.

If Democrats can’t get their legislation into reconciliation, it probably isn’t going to happen. Aside from a bipartisan infrastructure bill, Republicans have been ready and willing to filibuster most Democratic attempts at creating new policy. They even filibustered a raise of the debt limit this fall, taking the U.S. government right up to a shutdown and risking the United States defaults on its debts.

What she will rule on specifically

Whether Democrats’ wish list is directly applicable to spending and revenue. Democrats will of course argue it is, for a variety of reasons. On immigration, Democrats and Republicans actually debated with her about whether providing legal status to some 8 million people has a direct budget impact, the New York Times reported.

MacDonough decided that this path to citizenship wasn’t exactly related to budgetary matters and said Senate rules dictate it shouldn’t go into Democrats’ spending bill. A week later, Democrats brought her another plan on immigration to allow Dreamers to apply for citizenship. She decided that also didn’t fit the rules.

There’s a House parliamentarian as well, but this person has less sway over the chamber because the House often rewrites its rule with a simple majority vote, which Democrats have.

Can Democrats override the Senate parliamentarian?

Technically, yes. The Senate can overturn a parliamentarian’s ruling with 51 votes — Democrats have 50 and could call on Vice President Harris to break a tie.

But doing so is not a common practice in the Senate, so it’s much more controversial. (Both parties used this tool to erode the filibuster for presidential nominations.) NBC reports that Senate Minority Leader Mitch McConnell (R-Ky.) and Senate Majority Leader Charles E. Schumer (D-N.Y.) have an understanding that what MacDonough rules on dreamers, for instance, will likely stay.

Though Democrats are getting pressure from some in their left flank, like Rep. Ilhan Omar (D-Minn.), to ignore the parliamentarian and put Dreamer legislation in the spending bill anyway.

That’s not a comfortable position for the parliamentarian to be in, Ritchie said. MacDonough and her team have to sift through hundreds of pages of legislation, nonpartisan government budget objections and more to decide whether this huge bill meets the requirements of Senate rules and precedent.

But the Senate and the parliamentarian have a mutual respect for each other.

“Even as the Senate grumbles about it,” Ritchie said, “they are an institution that appreciates and completely relies on its parliamentarians.”

In the midst of this, MacDonough has been diagnosed with cancer and will be out for several weeks for treatment. Senate leaders say they are praying for her health.

This post has been updated.