(Jacquelyn Martin/AP)
Opinion writer

On Friday, the new House Democratic majority will roll out its first big contrast with President Trump, offering a major package of anti-corruption reforms that will showcase what the Democratic version of swamp-drainage looks like.

After winning a sweeping electoral victory in part on promises to clean up the Trump-era GOP’s Washington, Democrats hope to establish an ambitious blueprint for clean government in the face of Trump’s personal corruption and degradation of our institutions, and the GOP enabling of it all.

But efforts by Democrats to establish an affirmative agenda of their own will inevitably have to shade into their role of undertaking scrutiny of Trump’s corruption — and this is perhaps clearest in the case of Trump’s tax returns.

First, let’s note that the new reform package is impressive in scope. There are three main pillars to it. The first facilitates participation and protects voters, by expanding protections for voting rights, making voting easier and requiring nonpartisan commissions to replace partisan gerrymanders that dilute the power of voters.

The second seeks to defend our elections against torrents of outside cash, foreign interference and social media disinformation via limits on dark money and stricter disclosure rules on donations and ads, including digital, among other things. The third aims to clean up government itself through stricter ethics and transparency rules and limits on lobbying.

The combination of all these three reform tracks into one major package is something new, and it’s intentional.

“All of those three elements are fundamental to the idea that our democracy is open and responsive to the average person,” Rep. John Sarbanes (D-Md.), who’s playing a lead role spearheading the reforms, told me.

“If they can’t vote, they can’t register their judgment on who they want to see in office," Sarbanes said. “If there’s not a code of ethics in place, they’ll lack confidence that people in Washington act in a way that respects the public trust.” And limits on spending, Sarbanes noted, are meant to bolster confidence that the governing agenda isn’t being set by “special interests and big money.”

The provision on tax returns

One of the most interesting elements in the Democratic reform package is a provision that requires presidential candidates to release tax returns. Here’s how this will work, according to Sarbanes’s office: Once a major-party candidate is nominated at its national convention, that triggers a requirement that he or she release tax returns going back 10 years.

But what about Trump’s returns?

Politico recently reported that Democrats might be delaying their push to seek Trump’s tax returns. Speaker Nancy Pelosi has delegated this task to Ways and Means Chairman Richard Neal (D-Mass.). Neal’s office told Politico that he might want to lay a public case for seeking the returns first, and suggested he might be worried that going after them could imperil bipartisan relations, though the reporting on this was somewhat vague. The Politico story caused an explosion of online outrage.

In our interview, Sarbanes — who is also playing a key role in developing the Democratic response to Trumpian corruption — suggested to me that he thinks Democrats should make a serious bid for Trump’s returns without much delay.

“There needs to be strong oversight with respect to the financial situation of the president,” Sarbanes said. “People want to know what’s behind the curtain in terms of his finances. Having any committee of jurisdiction that can reach those issues move with real deliberation and timeliness is going to be important.”

The most likely way Democrats can get them released is by invoking a century-old tax code provision that empowers tax-writing committees to request the returns of any individual from the Treasury Department. Trump and the department are sure to fight this in court, setting up a protracted legal battle.

Sarbanes told me that Democrats must be prepared to use their oversight powers — including subpoena power — to get them if necessary. “There are tools in the majority’s tool kit,” Sarbanes said. “Subpoena is one of those. But I think there are others. There are things they can do to press the issue, and I expect that any committee with jurisdiction is going to look at what its options are.”

Democrats can’t back off

It still remains unclear how Democrats will proceed here. On the one hand, they clearly want to roll out this reform package as their first major affirmative statement of their own anti-corruption and pro-democracy agenda, one that stands on its own terms, not in opposition to Trump. Aides have said they want to debate the provision of their bill requiring future presidential candidates to release returns first, to lay a foundation for seeking Trump’s in particular. The desire to make this larger than Trump is understandable.

On the other hand, this should not turn into any kind of real delay. Getting Trump’s returns is imperative to establishing whether he has financial entanglements with Russia or Saudi Arabia or anyone else that cast doubt on the true motives behind his policies and his efforts to completely revamp the United States' international relationships for reasons that often appear mystifying and utterly baseless.

Democrats were elected in large part to provide a check on Trump’s corruption and shredding of democratic and institutional norms. Trump’s blithe refusal to release his returns is basically a big fat middle finger aimed at our norms and institutions, and even in a sense a straight-out declaration that he can damn well do all the self-dealing as president that he pleases. You, the public, will never be the wiser.

Yes, it will be very hard to get Trump’s returns, and yes, Trump will put up a protracted struggle over them. But this is a fight Democrats must wage, not to “get Trump,” as his defenders like to whine, but rather as a blow on behalf of the broader anti-corruption agenda that Democrats hope to stand for.

Read more:

Greg Sargent: Democrats will try to get Trump’s tax returns. But they need to do it right.

Nancy Pelosi and John Sarbanes: The Democratic majority’s first order of business: Restore democracy

Greg Sargent: Memo to Democrats: Don’t wring your hands about investigating Trump

The Post’s View: Trump breaks his tax returns promise — for the third year in a row

Jennifer Rubin: This is why every president must disclose his tax returns