President Trump said Monday that he will declare a national emergency next week to address the opioid epidemic and declined to express confidence in Rep. Tom Marino (R-Pa.), his nominee for drug czar, in the wake of revelations that the lawmaker helped steer legislation making it harder to act against giant drug companies.

Trump's remarks came amid widespread reaction across the political spectrum to a Washington Post/"60 Minutes" investigation that explained how Marino helped guide the legislation, which sailed through Congress last year with virtually no opposition.

Trump said "we're going to be looking into" the investigation, while many Democrats and at least one Republican called for modification or outright repeal of the law. Democrats also urged Trump to drop Marino as his pick to lead the Office of National Drug Control Policy.

Speaking in the White House Rose Garden, Trump defended Marino as "a very early supporter of mine" and "a great guy." He said that he had seen the reporting in question and that the White House would review the information.

Trump said he would have a "major announcement, probably next week" about how his administration plans to tackle opioid addiction in the United States, a "massive problem" that he wants to get "absolutely right."

"This country and, frankly, the world has a drug problem," he said. "We're going to do something about it."

Asked by a reporter whether he would be declaring the epidemic a national emergency, as he first promised in August but has not yet done, Trump said, "We're going to be doing that next week."

A presidential declaration could allow the administration to remove some bureaucratic barriers and waive some federal rules governing how states and localities respond to the drug epidemic. One such rule restricts where Medicaid recipients can receive addiction treatment.

The president also said he had not yet spoken with Marino about the Post/"60 Minutes" report, but if he determines that Marino's work was detrimental to the administration's goal of combating opioid addiction, "I will make a change."

[Read the investigation: How the drug industry derailed the DEA’s war on painkillers]

On Monday, Democrats called on Trump to quickly discard Marino in the wake of the report, which detailed how a targeted lobbying effort helped weaken the Drug Enforcement Administration's ability to go after drug distributors, even as opioid-related deaths continue to rise.

Senate Minority Leader Charles E. Schumer (D-N.Y.) said nominating the Pennsylvania lawmaker for drug czar "is like putting the wolf in charge of the henhouse. The American people deserve someone totally committed to fighting the opioid crisis, not someone who's labored on behalf of the drug industry."

Sen. Joe Manchin III (D-W.Va.) said he was "horrified" to read details of the investigation and called for Trump to drop Marino because "there's no way that in having the title of the drug czar that you'll be taken seriously or effectively by anyone in West Virginia and the communities that have been affected by this, knowing that you were involved in something that had this type of effect."

Manchin told "CBS Evening News" on Monday that the bill's intent was "camouflaged" so that "all of us were fooled. All of us. Nobody knew!" He added, "That bill has to be retracted, has to be repealed."

Marino was first floated as a potential DEA administrator last spring but withdrew from consideration, citing a family illness. The White House formally nominated him for the post in September. The Senate Judiciary Committee has yet to set a date for his confirmation hearing because Marino has not sent back answers to a written questionnaire that all nominees must complete before a hearing, a spokesman said.

Members of the committee didn't immediately answer requests for comment on the nomination, or declined to comment. Ultimately, Marino could be confirmed by the Senate with a simple majority vote.

Across Capitol Hill, congressional Democrats and at least one Republican, Rep. Brian Fitzpatrick (Pa.), announced plans to address the report's findings.

Sen. Claire McCaskill (D-Mo.) said Monday that she would introduce legislation to repeal the Ensuring Patient Access and Effective Drug Enforcement Act of 2016. The law, she said, "has significantly affected the government's ability to crack down on opioid distributors that are failing to meet their obligations and endangering our communities."

McCaskill, as the top Democrat on the Senate Homeland Security and Governmental Affairs Committee, has used her perch to probe opioid manufacturers and is pushing them for sales and marketing materials, studies of potential addictions, and whether the firms are donating to third-party advocacy groups that champion their work. It was unclear Monday afternoon how much support her bill would receive and whether it would be taken up for a vote in the GOP-controlled House and Senate.

Sen. Richard Blumenthal (D-Conn.) also called for Trump to withdraw Marino's nomination, saying in an interview that "the head of that office is supposed to be a watchdog, not a lap dog. He obviously is much more an industry representative than he is a whistleblower or watchdog."

"It will be ugly" if Trump continues with the nomination, Blumenthal said.

In the House, at least two Democrats — Reps. Gerald E. Connolly (Va.) and Kyrsten Sinema (Ariz.) — were working on bills that would rescind the thresholds put in place by Marino's bill and give the DEA more authority to suspend a distributor's license. Sinema is partnering with Fitzpatrick.

Rep. Peter Welch (D-Vt.), an original co-sponsor of Marino's legislation, said he supported the bill on behalf of a small drug distributor in Burlington, Vt., that had concerns about how the DEA worked with drug companies. He called on the House Oversight and Energy and Commerce committees to hold hearings on the legislation that would include testimony from current and former DEA officials.

One of Marino's home-state senators, Sen. Robert P. Casey Jr. (D-Pa.), is withholding judgment on Marino's nomination, but a spokesman for the senator said that he believes the congressman "should be asked to address this matter." Casey also believes that the legislation Marino backed "should be repealed immediately and DEA's authority to hold drug distributors to tough standards should be restored," said spokesman John Rizzo.

Manchin, McCaskill and Casey face reelection next year in rural states that Trump won. Despite their concerns, they did not oppose the legislation when it passed in the Senate last year by unanimous consent. While her staff initially said McCaskill was absent on the day of the vote due to breast cancer treatment, the senator was in Washington and didn't object to the bill.

She told CBS News on Monday, "It's not unusual for something like this [bill] to roll through without much fanfare."

Manchin said in the Post interview that his aides responsible for tracking drug policy had raised concerns about Marino's legislation as it worked its way through Congress last year.

"They had questions and they had concerns from the beginning, but they were laid to rest by the DEA. We're going to find out how that could happen and why," Manchin said.

As an alternative to Marino, Manchin suggested that Trump consider nominating Joseph T. Rannazzisi to head the DEA. Rannazzisi ran the DEA division responsible for regulating the drug industry and led a decade-long campaign of aggressive enforcement until he was forced out of the agency in 2015.

If Trump prefers to nominate a partisan figure, "we can find a Republican who has a passion because of the devastation to their own family. That won't be hard to find in America, I can assure you that," Manchin said.

The office of Sen. Patrick J. Toomey (R-Pa.), meanwhile, said that the senator supported Marino and that it was "ridiculous" to think the congressman and the Obama administration "conspired to exacerbate the opioid crisis. Every member of Congress supported the measure in question and the DEA did not voice any objections. If there is an unintended or unforeseen consequence of this legislation, Senator Toomey is open to working across the aisle to find a solution."

Fallout from the investigation also has spread to electoral politics. Rep. Marsha Blackburn (R-Tenn.), who is running for the Senate in a state that has been hit hard by the opioid crisis, is also fielding attacks for being a lead sponsor of Marino's bill.

James Mackler, the Senate race's Democratic front-runner, criticized Blackburn for her involvement, saying in a statement late Sunday: "I'm running for U.S. Senate because Tennesseans need a senator that will stand up for them rather than catering to special interests and corporate lobbyists.

"That Congresswoman Blackburn would champion legislation like this while Tennesseans face an opioid epidemic is all one needs to know about her priorities," he said.

[Rep. Marsha Blackburn draws campaign fire for shepherding bill that undercut DEA]

In April 2016, a handful of members of Congress, allied with the nation's major drug distributors, prevailed upon the DEA and the Justice Department to agree to the more industry-friendly legislation, undermining efforts to stanch the flow of pain pills, according to the Post/"60 Minutes" investigation. The DEA had opposed the effort for years.

The law was the crowning achievement of a multifaceted campaign by the drug industry to weaken aggressive DEA enforcement efforts against drug distribution companies that were supplying corrupt doctors and pharmacists who peddled narcotics to the black market. The industry worked behind the scenes with lobbyists and key members of Congress, pouring more than $1 million into their election campaigns.

The chief advocate of the law that hobbled the DEA was Marino, who spent years trying to move it through Congress. It passed after Sen. Orrin G. Hatch (R-Utah) negotiated a final version with the DEA.

Hatch defended his support of the legislation and Marino on Monday, saying in a statement that he "does not believe one flawed report should derail a nominee who has a long history of fighting illegal drug use and of helping individuals with chronic conditions obtain treatment."

"Let's not ignore the full story here in the rush toward easy politics," Hatch added.

DEA Chief Administrative Law Judge John J. Mulrooney II has written a draft law review article critical of the legislation, saying it makes it "all but logically impossible" for the agency to take action against drug companies that fail to comply with federal law.

Hatch responded to the article, saying: "I'm disappointed that, after I spent months negotiating in good faith with DEA and DOJ, the bill is now being attacked by a DEA official who had no involvement in the negotiations. Members of Congress rely on agency experts to apprise them of potential problems with legislation. If the concerns Judge Mulrooney raises now were present in the agency at the time the bill was being negotiated, agency staff should have asked me to hold off on moving the bill. They did not do so. Instead, they agreed on compromise language that the Senate would move forward with. DEA should not be able to have it both ways."

Besides the sponsors and co-sponsors of the bill, few lawmakers knew the true impact the law would have. The White House was equally unaware of the bill's import when President Barack Obama signed it into law, according to interviews with former senior administration officials.

The DEA and the Justice Department have denied or delayed more than a dozen requests filed by The Post and "60 Minutes" under the Freedom of Information Act for public records that might shed additional light on the matter. Some of those requests have been pending for nearly 18 months. The Post is suing the Justice Department in federal court for some of those records.

An earlier version of this article reported that Sen. Claire McCaskill (D-Mo.) was absent from Congress at the time the DEA legislation was passed due to treatment for breast cancer. The senator's staff, which had provided incorrect information about her whereabouts, later said she was present when the bill was passed by unanimous consent. The article has been updated.

READ MORE:

The full investigation into the drug industry's triumph over the DEA

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Joe Rannazzisi: The DEA official who fought the drug companies and lost