Ron Sachs-Pool/Getty Images President Donald Trump dismantles the Department of the Interior's Stream Protection Rule, meant to protect waterways from from coal mining operations, at the White House on Feb. 16, 2017.

WASHINGTON ― While President Donald Trump distracts the public with his angry tweets, Republicans in Congress have been busy undoing federal regulations that agencies have been working on for years.

GOP lawmakers are dismantling regulations they deem overreaching and burdensome using an obscure law known as the Congressional Review Act, or CRA, which can be used to undo any regulation within 60 days of its finalization. The law, passed in 1996, also bars agencies from writing a “substantially” similar rule after the initial rule has been blocked ― a major concern for legal experts and advocates.

The CRA came to be under legislation pushed by then-Speaker Newt Gingrich (R-Ga.). Lawmakers wanted an easier way to undo regulations, even though agencies can only issue them according to statutes written by Congress.

Congress had only used the CRA once before Trump took office, which is another reason people are concerned about its implications. There isn’t a whole lot of legal precedent concerning how and when it should be used.

In 2001, Republicans used the CRA to undo a Clinton-era regulation creating new workplace ergonomics rules to prevent repetitive injuries. The agency that wrote the rule ― the Occupational Safety and Health Administration ― never touched ergonomics standards again.

Ergonomics may sound silly, but the rules weren’t about desk jockeys dealing with carpal tunnel syndrome. Think more like meat-packers crippled by repetitive injuries ― those are the people the regulation would have helped the most.

“Ergonomic injury is very common among poultry processing workers, both because repetitive knife cuts and hoisting heavy birds on and off the assembly line cause debilitating carpal tunnel,” explained University of Maryland law professor Rena Steinzor, formerly president of the Center for Progressive Reform.

When the Obama administration considered allowing faster line speeds at poultry plants in 2012, labor groups opposed the move as dangerous and urged OSHA to write new a new rule to make the work safer; poultry plant workers already suffer injuries at twice the rate of the general workforce.

Steinzor, who has testified before Congress on regulations, credits the 2001 CRA resolution targeting ergonomics as the reason OSHA decided not to write a new rule, though the agency didn’t cite it in its formal denial of petitions to take action on behalf of poultry workers.

OSHA “cowered,” said Steinzer. “It was battered. It stopped dealing with ergonomics.”

It may very well be the ultimate block on modernizing workplace standards. Celine McNicholas, Economic Policy Institute

Republicans’ desire to rip up Obama-era rules is no surprise, but using the CRA to do so could have a chilling effect on federal agencies that lasts for years.

In the last month, the House has pushed through 13 “resolutions of disapproval” reversing Obama-era regulations, including a Labor Department rule blocking contractors that have repeatedly violated workplace standards from receiving new contracts. The Senate is expected to take up that measure soon, and the House is also eyeing other Labor Department regulations that qualify for CRA action.

What makes passing a disapproval resolution under the CRA so easy is that you only need a simple majority to do it, meaning Democrats in the Senate can’t use a filibuster to stop it.

“The most interesting and troubling thing about this is that it may very well be the ultimate block on modernizing workplace standards,” said Celine McNicholas, labor counsel for the Economic Policy Institute.

The lack of precedent when it comes to the use of the CRA creates a tricky situation for all branches of government, since the agencies are still required to issue rules on specific issues, but can’t do so in a way that replicates their previous rule. The CRA states that a rule “may not be reissued in substantially the same form,” and that the agencies cannot issue “a new rule that is substantially the same” ― unless Congress passes a new law requiring a rule on that subject.

McNicholas noted that because the CRA has been used only once before, there has not been a judicial review, nor is there any case law defining how agencies should proceed.

“We’re in uncharted territory here,” she said.

Craig Warga/Bloomberg via Getty Images An employee packs ground turkey in Hamilton, New Jersey, on Oct. 21, 2013. Meatpackers are susceptible to injuries, but Republicans undid a workplace ergonomics rule that would have protected them using the Congressional Review Act.

Even the 60-day limit on using the CRA is fuzzy, because the time frame is 60 legislative days after finalization, not actual days. The Congressional Research Service reported last fall that any rule agencies finalized after May 30 last year is potentially subject to disapproval ― which means as many as 145 rules are subject to potential repeal.

The main reason the CRA is not used more often is that presidents generally don’t want to overturn rules their agencies have created, and will veto any “resolutions of disapproval” that make it through Congress. Republicans passed five CRAs between 2009 and 2016, but Obama vetoed all of them.

It’s the time period shortly after the White House switches parties and the reigning party controls both chambers of Congress when the stars align for the CRA.

And it’s not just labor rules Republicans are throwing out. In the first few weeks of the Trump administration, Congress has passed CRAs undoing a Social Security Administration rule meant to keep mentally ill people from buying guns, and a Securities and Exchange Commission rule requiring oil, gas and mining companies to disclose their payments to foreign governments.

The foreign disclosure rule in particular puts the SEC in a bit of a bind, because under the Dodd-Frank Wall Street Reform and Consumer Protection Act Congress passed in 2010, companies must provide this kind of information to regulators.

Sen. Ben Cardin (D-Md.), who co-authored the law, expressed great frustration with his Republican colleagues who helped write Dodd-Frank but then voted in support of the CRA chopping up the SEC rule. Cardin said he talked to Republican colleagues who had supported that piece of Dodd-Frank, hoping to convince them to flip their vote. It didn’t work.

“What the Senate did with the CRA, what Republicans did on a straight party-line vote, is outrageous,” Cardin said. “It’s an abuse of the CRA, compromises America’s leadership, and delays substantially ― and perhaps even the quality ― of the disclosures that will have to take place.”

Cardin admitted that the SEC took too long to write the rules Dodd-Frank required, as it’s been almost seven years since Congress passed the law. But undoing them now, Cardin said, would damage the country’s international credibility when it comes to fighting corruption, and would make it more difficult for the SEC to find another avenue for fulfilling the Dodd-Frank mandate.

But the SEC will need to try, Cardin said, because he isn’t holding his breath in hopes that Congress will advance any other anti-corruption legislation anytime soon.

What the Senate did with the CRA, what Republicans did on a straight party-line vote, is outrageous. Sen. Ben Cardin (D-Md.)

Environmental advocates have been some of the loudest opponents the CRA. Republicans have already targeted three Interior Department regulations; Trump signed a bill undoing regulations to protect waterways from from coal mining operations on Thursday. Two other bills targeting rules from the Interior Department’s Bureau of Land Management are expected to come up for a vote in the Senate when lawmakers return on Feb. 27.

One of those BLM rules cracks down on the amount of methane, a potent greenhouse gas, that natural gas producers are allowed release in drilling operations on federal land. The other rule updated BLM guidelines on when and where to allow development on federal lands and provided more opportunities for the public to weigh in on those decisions.

If the Senate follows the House in undoing both rules, environmental advocates will inevitably challenge agencies to write similar regulations ― opening the door to potential lawsuits.

“It’s unfortunate that they have decided to take a tool that has such a lack of precedence and that is so blunt and extreme,” said Josh Mantell, energy campaign manager with the Wilderness Society. “We understand there may be issues with some of these regulations, but the idea that you’d throw the entire thing out and not allow anyone to move forward just traps us in the past.”

Mantell added that there could be some loopholes for agencies if they want to write a similar rule later. They could issue the regulation under other statutes, or a new administration could direct a different agency with similar jurisdiction to take it on. Still, he said, it’s unfortunate that “five-year processes, with an extreme amount of public engagement, are wiped out through the CRA.”

BURGER/PHANIE via Getty Images A urinalysis rule could also fall victim to the Congressional Review Act.

One of the rules Republicans put up for a disapproval vote in the House last week came as a surprise to a lot of people, since the rule hadn’t received any significant attention when it was issued. It has to do with urine.

In 2012, Congress passed a law that would allow states to make people filing for unemployment insurance submit to drug tests. Democrats hated the idea, but they agreed to the provision in exchange for getting Republican support for an expensive extension of long-term unemployment insurance.

Democrats didn’t agree to allow states to just do whatever they want, however. As a compromise to the compromise, the legislation said states could only test people in occupations for which such testing is common, such as jobs with a public safety component. And the bill instructed the Labor Department to come up with a regulation controlling how states decide which workers should be subject to urinalysis. Democrats were confident the department wouldn’t allow states to test too many people.

But Republicans neglected to give the Labor Department a deadline for writing those rules. The agency took its time, and didn’t release a proposed rule until 2014. Congressional Republicans and Wisconsin Gov. Scott Walker (R) complained that the draft regulation wouldn’t let states drug test enough people. But the rule only received 16 public comments; contentious rules can get tens of thousands of comments.

The Labor Department issued the final version of the regulation last August ― which is within the timeline for disapproval under the CRA, according to the Congressional Research Service. The delay in drafting the rule could guarantee its demise, as Republicans seek to expand drug testing for the poor and jobless.

A former Labor Department official said the agency was mindful of the CRA, but had no way of knowing exactly when the cutoff would be.

Also, nobody expected Trump to be president.

“When you have a rule with 16 comments and you’re making significant changes to address those comments, we didn’t think of this as a CRA target,” the former official said.

Now that the CRA resolution targeting urine passed the House, the Senate will need to vote before it can head to Trump’s desk.

Theoretically, once the urinalysis rule is gone, the Trump Labor Department could reissue a new version that Republicans like better. The CRA language about what constitutes “substantially” similar regulations has never been tested, and it doesn’t say who is the arbiter of what is too similar. It might be up to Congress.

But it’s also possible that Congress strikes the rule and the Labor Department can’t issue a new one. Republicans could try to pass a new drug testing law, but Senate Democrats would probably keep that from happening. Then states will be left with no authority to drug test unemployment claimants at all.

The use of the Congressional Review Act “is only the first step” for Republicans when it comes to undoing regulations, said Steinzor.

“We’ve gone DefCon 1,” she said. “There’s worse still to come.”

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