Rep. Tom Marino (R-Pa.), is seen in a 2016 photograph taken during testimony before a House committee on the heroin epidemic and parental substance abuse. (Mark Wilson/Getty Images)

Forty-four state attorneys general asked Congress on Tuesday to repeal a law that effectively strips the Drug Enforcement Administration of potent weapons against large drug companies that have allowed hundreds of millions of pain pills to spill onto the black market.

The state law enforcement officials, many from places hit hard by the opioid epidemic, signed a letter from the National Association of Attorneys General to Republican and Democratic leaders in the House and Senate. Congress approved the law by unanimous consent, without a vote in either chamber, in 2016.

The Washington Post and “60 Minutes” revealed in a joint investigation last month that an early version of the legislation had been written by a drug industry lawyer and shepherded through the House by Rep. Tom Marino (R-Pa.) for two years. Sen. Orrin G. Hatch (R-Utah) negotiated the final version of the bill with the DEA. Two days after the media reports, Marino withdrew his nomination to be the nation’s next drug czar.

“The Ensuring Patient Access and Effective Drug Enforcement Act neither safeguards patient access to medication nor allows for effective drug enforcement efforts,” the bipartisan group of attorneys general wrote. “We urge you to repeal the act so that the public is protected and drug manufacturers and distributors may be held accountable for their actions.”

Marino defended the legislation, noting that it was rewritten by a bipartisan collection of senators and signed by President Barack Obama.

“This carefully crafted legislation was put together the way Americans want to see the process operate: transparent and with both parties working together to solve a complex problem,” Marino said in a statement. “We must balance the needs of patients — particularly those at end of life who sometimes find access to medicine a desperate challenge — and the needs of law enforcement.

“As I’ve done over my career as a prosecutor and a member of Congress, if law enforcement, in this case the DEA, needs additional resources or changes to legislation we will work with them to ensure they have the tools necessary.”

Hatch also defended the law.

“Calls for repeal are premature and frankly irresponsible before we have had a full airing of the bill and its actual effects,” he said in a statement. “Critics of the bill chastise Congress for passing the bill without a full awareness of what the bill would do. Ironic, then, that critics are now rushing to repeal the bill without any data on the bill’s impact or official word from DEA on how the bill has affected enforcement efforts.”

Rep. Greg Walden (R-Ore.), chairman of the House Energy and Commerce Committee, which approved the House version of the bill, said: “I welcome feedback from the Attorneys General as we continue working to combat the opioid crisis. It is of the utmost importance to this committee that we better understand how any legislative actions can improve the agency’s ability to prevent potentially addictive drugs from reaching our communities.”

The investigation showed that by defining language in the Controlled Substances Act of 1970, drug industry supporters in Congress upended more than four decades of DEA practice. The new law made it virtually impossible for the DEA to impose an “immediate suspension order” on distributors of highly addictive painkillers that had failed to report suspicious orders of drugs such as oxycodone placed by pharmacies and other dispensers.

“This law was never intended to decrease the DEA’s enforcement against distributors and other registrants,” the Healthcare Distribution Alliance, which represents drug distributors, said in a statement. “If it is determined that there have been any unintended consequences that undermine the DEA’s ability to enforce the law and take legitimate actions to prevent prescription drug abuse, we stand ready to work with Congress to address them in all appropriate ways including legislative action.”

DEA Chief Administrative Law Judge John J. Mulrooney II wrote in an upcoming law review article that it is now “all but logically impossible” for the DEA to suspend a drug company’s operations for failing to comply with federal law.

The attorneys general made the same point, citing Mulrooney’s opinion.

Some Democratic lawmakers, including Sen. Claire McCaskill (Mo.), have called for repeal or amendment of the law in the wake of the media reports, and Sen. Charles E. Grassley (R-Iowa), chairman of the Senate Judiciary Committee, has said he will hold an oversight hearing. But efforts to repeal the bill have stalled because no key Republicans have signed on.