Attorney General Merrick Garland and Homeland Security Secretary Alejandro Mayorkas are set to testify on Wednesday on the administration’s efforts to crack down on domestic extremism as Congress is scrutinizing law enforcement’s actions in the leadup and aftermath of the Capitol riot.

Their appearance before the Senate Appropriations Committee comes amid a flurry of congressional hearings examining the Jan. 6 attack on the Capitol. The hearing also highlights a broader debate over the federal approach to domestic terror, which has lawmakers and civil rights groups weighing in on whether the U.S. needs new statutes or designations to respond to increasing threats.

Garland, who helped prosecute the Oklahoma City bombing early in his legal career, has emphasized his commitment to combating domestic extremism since becoming attorney general. Last week, he testified that foreign and domestic terrorism threats “keep me up at night.”

He told the House Appropriations Committee that President Biden’s “skinny” budget proposal allocating $35.2 billion for the Justice Department would support its efforts to protect national security from both foreign and domestic terror threats, highlighting the $95 million requested increase toward domestic terrorism prosecutions and investigations.

“Virtually every morning I get a briefing from the FBI in one or the other or both of those areas,” Garland said. “Since the last time I was in the Justice Department, when both were concerns as well, the lethality of weapons available to these kinds of terrorists both foreign and domestic has increased. The consequences of the internet and encryption means that they can send information and make plans more swiftly and in greater secrecy than could have been done before.”

The Justice Department has brought more than 400 cases against Capitol rioters since Jan. 6, with charges ranging from disorderly conduct to assaulting a police officer to conspiracy. But lawmakers have begun to question whether law enforcement could have done more to prevent the mayhem that left four people dead and led to the suicides of at least two police officers.

Mayorkas has vowed that the Department of Homeland Security will step up its monitoring of domestic extremist groups and their online organizing and recruitment efforts.

“I have directed an expansion of our analytic focus, including to more comprehensively assess how extremist actors exploit and leverage social media and other online platforms, and how those online activities are linked to real-world violence,” he told the House Homeland Security Committee in March.

Democrats have also been pressing the administration to prioritize addressing right-wing extremism and exploring whether legislation is needed to better enable law enforcement to go after violent groups and lone wolves. Garland and Mayorkas may face questions from the committee about whether their agencies are fully equipped to handle the threat.

In January, just two weeks after the Capitol riot, a group of House Democrats introduced a bill that would make institutional reforms to the law enforcement and intelligence agencies to assist the federal government’s ability to crack down on such groups.

“In the wake of the domestic terrorist attack on our Capitol two weeks ago, it is painfully clear that the current approach to addressing the real and persistent threat posed by white nationalism and similar ideologies is not working,” Rep. Jerrold Nadler (D-N.Y.), a co-sponsor of the bill and the chairman of the House Judiciary Committee, said in a statement at the time. “We must not allow hate crimes and domestic terrorism to continue unchecked.”

The federal terrorism statute has a number of sections specifically dealing with foreign terrorism, while domestic terrorists have often been prosecuted through a number of state laws.

Some believe the federal government should come up with a domestic terrorism statute to prevent bad actors from falling through any potential gaps in the existing criminal statutes and provide more resources to state law enforcers.

“This is a gap that my Department has used our state laws to fill, but to fully combat domestic terrorism across the country, changes to federal criminal laws must be made,” Michigan Attorney General Dana Nessel (D) told a House Homeland Security subcommittee in March. “Moreover, because we are on the front line of this battle, federal funding is needed for state law enforcement offices — like mine — so that we can dedicate staff and resources to this cause.”

But any new law to increase law enforcement capabilities is likely to face stiff opposition from progressives and civil rights advocates who see echoes of the post-9/11 era’s expansion of the national security state or the surveillance of civil rights groups and political dissidents during the 20th century.

More than 150 different civil rights groups signed a letter in January urging the Justice Department to crack down on domestic extremism “without causing further harm to communities already disproportionately impacted by the criminal-legal system.”

Margaret Huang, president and CEO of the Southern Poverty Law Center, said domestic terror investigations have often targeted Black, Middle Eastern and South Asian communities.

“The worry is that these laws, which might allow infringement on freedom of speech or association, would target these communities who already are facing a lot of other discriminatory treatment and actually make things worse,” she said.

But she said institutional focus on international terrorism and a lack of political will have hindered the FBI from devoting the same attention to domestic extremism.

“We have the existing power and authorities and haven’t used them appropriately,” she said.

It’s still unclear whether the Biden administration would back any effort to add criminal penalties or create designations for domestic extremists. A Justice Department official told Congress last month that the agency is weighing whether to make a legislative proposal along those lines, according to Bloomberg.

“The question we’re really wrestling with is: Are there gaps?” Brad Wiegmann, deputy assistant attorney general with the Justice Department’s national security division, said during a House Appropriations subcommittee hearing. “Is there some type of conduct that we can envision that we can’t cover or would it be an otherwise benefit in having something else other than what we’re having now?”

Mayorkas and Garland might also face questions into how they classify the various types of domestic extremists.

Senate Judiciary Democrats had asked the FBI to be more specific in how it breaks down racially motivated violent extremists, arguing the broad term “obfuscates the threat posed by violent white supremacists.” They also asked for a breakdown of the anti-government extremist label and the number of investigations focused on right-wing groups versus those on “Antifa or similar ideologies.”

Meanwhile, the GOP has often asked national security leaders what they are doing to combat antifa demonstrators.

FBI Director Christopher Wray has repeatedly said white nationalists represent the bulk of the bureau’s domestic terror cases.

Simon Clark, a senior fellow with the Center for American Progress, said there is a difference between politicians who “want to do more about what agencies say is the major threat today and politicians who look at the data and want to emphasize action on what is not the most important threat today.”

“We need more and better quality data so that we depoliticize that, so we can be clear about what the actual threat is,” he said.