Another influential Chicago Democrat faces criminal charges for using his office to rig the political system and scam the public.

Chicago State Rep. Luis Arroyo told an unnamed state senator “this is the jackpot” when he slipped him a check for $2,500, with the promise of more each month for up to a year, in exchange for support on gambling legislation that benefited his lobbying client, the Associated Press reports.

The senator was working as an informant with the FBI.

In Illinois, lawmakers can simultaneously work as lobbyists, and Arroyo is a lobbyist registered with the Chicago City Council to promote the legalization of online video gambling “sweepstakes” games.

“This is just a large loophole here,” Common Cause Illinois Executive Director Jay Young said. “It’s the quintessential backroom deal where people with power are making deals to benefit themselves.”

The 65-year-old lawmaker faces one count of bribery after investigators allege he promised to pay the state senator $2,500 a month to support the gambling legislation and met with the senator at a restaurant in Skokie in August to deliver the first check, CBS Chicago reports.

The senator was an FBI informant and recorded the conversation.

“I’m going to give you this here,” Arroyo said, according to court records. “This is, this is, this is the jackpot.”

Arroyo also told the senator he expected some kickbacks himself for working his “ass off” on behalf of his client.

The federal complaint did not name the senator involved, but news reports claim Sen. Terry Link, a Democrat from Vernon Hills, is cooperating to reduce his punishment for filing false tax returns in 2016, according to CBS Chicago.

Arroyo was released from jail on a personal recognizance bond after an initial court appearance on Monday, but ignored reporters on his way out.

He faced immediate calls for his resignation from both Republicans and Democrats in the General Assembly, but has so far resisted.

On Tuesday, House Speaker Michael Madigan filed paperwork to launch an investigation, the first step toward expelling Arroyo from the House. Such an expulsion, which requires a vote of at least 79 of the chamber’s 118 members, has only occurred twice before in the last 100 years, the AP reports.

Chicago Democrat Derrick Smith was the last lawmaker expelled from the House in 2012 for accepting a bribe.

“We swear an oath to serve the people of Illinois that shouldn’t be compromised either in fact or in appearance by a paid contract to take action that overlaps with what our legislative duty is,” House deputy minority leader Tom Demmer said.

Demmer announced legislation to prohibit legislators from working as lobbyists at any level of government, and to require all lobbyists to register with the state.

Others, including Senate President John Cullerton, are suggesting a joint House and Senate review of ethics laws much like the one conducted in the wake of Gov. Rod Blagojevich’s impeachment in 2009, CBS Chicago reports.

“There are clearly some issues we’re dealing with that were not addressed 10 years ago with regard to lobbying,” he said.

Arroyo faces up to a decade in prison, if convicted.

He’s only one of several Chicago politicians to face federal charges this year. Others include Ald. Edward Burke, who faces racketeering, Bribery, and attempted extortion, as well as Illinois state Sen. Thomas Cullerton, who stands charged with embezzling $250,000 from the Teamsters. Federal investigators have also raided the home and offices of state Sen. Martin Sandoval and Ald. Carrie Austin, but no charges have been filed in those cases, according to the news site.