WASHINGTON — A few weeks before he left the U.S. Senate in January, Pat Toomey helped block the Enablers Act, a bipartisan proposal designed to curtail corruption and money laundering.

Since then, the Pennsylvania Republican has taken jobs in a pair of industries — private equity and cryptocurrency — that lobbied aggressively against the bill, sparking calls to overhaul ethics laws and address what's known as "the revolving door" between government and the private sector.

Citizens for Responsibility and Ethics in Washington, a watchdog group, said Toomey's new gigs — he's a director of Apollo Global Management and an adviser to Coinbase — came not long after he fought against the Enablers Act.

Proponents of the legislation initially tried to package it with the National Defense Authorization Act, which sets military policy and spending and is seen as a must-pass measure for Congress every year. The bill would have required certain financial "enablers," including law firms, investment adviser firms and crypto companies, to "conduct basic anti-corruption checks before they facilitate the flow of money into and around the United States," CREW said.

Virginia Canter, CREW's chief ethics lawyer, said most employment rules for outgoing lawmakers deal primarily with lobbying. Generally, former House members cannot lobby for one year and senators for two years after leaving office. Similar restrictions cover certain congressional staff members.

"But there's nothing that bars somebody from going to work or accepting compensation from anybody who lobbied their committee or lobbied them personally," Ms. Canter said.

Public filings show Coinbase lobbied against the Enablers Act, while Apollo lobbied on the NDAA. Toomey, who was the ranking member of the Senate Banking Committee and has invested in crypto, blocked the Enablers Act's inclusion in the NDAA last December. Brad Grantz, the GOP staff director for the committee, said at the time that Toomey believed there should be a hearing and greater discussion on the bill "before expanding [the U.S. Treasury's] authority yet again" by adding the Enablers Act into the NDAA.

Toomey could not be reached for comment last week. Neither Apollo nor Coinbase responded to requests for comment.

"Pat has a reputation for independent thinking and leadership experience in policy areas relevant to Apollo's business," Marc Rowan, Apollo's CEO, said in February. "His appointment also underscores our commitment to best-in-class corporate governance, with oversight from a board that is two-thirds independent and representative of diverse perspectives and deep experience across a variety of sectors and industries."

Coinbase brought on Toomey, a former Wall Street banker, in May, along with former U.S. Reps. Tim Ryan, D-Ohio, and Patrick Maloney, D-N.Y. Coinbase is fighting charges by the U.S. Securities and Exchange Commission that it's unlawfully facilitated the trading of crypto asset securities since at least 2019. On Thursday, the company asked a federal court to dismiss the charges, calling the SEC's lawsuit an "extraordinary abuse of process."

Ms. Canter, who worked in the administrations of former Presidents George W. Bush, Bill Clinton and Barack Obama, said the lobbying restrictions for former lawmakers are "only one side of the coin."

"There's some recognition they may have to go out and earn a living," she said. "But we certainly don't want them taking actions that could violate the public trust and potentially curry favor with prospective clients or employees."

CREW has called for a "cooling-off period" that would bar former lawmakers and executive branch officials from taking jobs with companies that have lobbied them or their committees for at least two years after leaving office.

In 2015, former U.S. Rep. Rod Blum, R-Iowa, introduced the No Golden Parachutes for Public Service Act, which would make the temporary lobbying restrictions for former lawmakers permanent.

And in 2018, U.S. Sen. Elizabeth Warren, D-Mass., introduced the Anti-Corruption and Public Integrity Act, which would overhaul not only lobbying and ethics rules but campaign finance and post-employment restrictions. The bill has been reintroduced multiple times since then.

Former President Donald Trump imposed a five-year lobbying ban for administration officials, but revoked the ban just before leaving office.

"Federal efforts to restrict the revolving door have been extensive but ineffective," Public Citizen, an advocacy group, wrote in a 2019 report that said almost two-thirds of former members of Congress worked as lobbyists, consultants, or in business or trade groups that seek to influence federal policy.

"Despite ostensibly having restrictions in place, the revolving door continues to spin at an alarming speed, raising serious concerns about 'regulatory capture' of agencies by the same business interests they seek to regulate, and creating an uneasiness about whose interests Congress is defending," the group said in its report.

State governments often do a better job than the feds of addressing the revolving door, Public Citizen said.

Starting this year, former lawmakers and judges in Florida are barred from lobbying for up to six years after they leave office.

In Pennsylvania, the revolving door section of the state's Ethics Act bans public officials and public employees from lobbying their former government body for one year after leaving office.