A vote on Friday by the Maine Commission on Governmental Ethics and Election Practices, determined there will be an investigation into the source of $4.3 million in funding for a York County casino proposal headed for a statewide referendum in November.

Attorneys for the casino backers, however, rejected subpoenas for the investigation presented by ethics commission Executive Director Jon Wayne, according to the Associated Press.

Leading the referendum campaign is Lisa Scott, sister of controversial gambling entrepreneur Shawn Scott, who is responsible for organizing a referendum which led to Hollywood Slots in Bangor more than a decade ago. Immediately after Scott won at the ballot box, he sold the casino license to Pennsylvania-based casino and racetrack operator Penn National Gaming, Inc. (NASDAQ: PENN).

The casino proposal is headed for a statewide referendum in November after the second attempt by backers managed to collect enough voter signatures in January to force the vote. The ethics commission staff, however, reportedly says the $4.3 million didn’t come from the Scotts but instead came from loans from Tokyo and Las Vegas-based entities.

This after in May, Daniel Riley, a veteran State House lobbyist representing the company behind the proposed casino, reportedly sent a letter to the chairmen of the legislative committee charged with overseeing gambling in Maine that he was mistaken when in March he told a legislative committee that he was working for a Saipan-based company linked to Shawn Scott. At the time, Riley reportedly told the legislative committee that he was actually hired by a different company and that he was unaware of who the owner was.

The casino initiative includes language that limits applications for the southern Maine casino license to be only “from an entity that owned in 2003 at least 51 percent of an entity licensed to operate a commercial track in Penobscot County.” While that language links the effort to Shawn Scott’s Nevada-based Capital Seven LLC, it is unclear what entities are bankrolling the initiative and who owns them.

In late 2015, the effort to bring another casino to the northeasternmost U.S. state began with a petition gathering effort to get the question on the 2016 ballots. The effort was led by Lisa Scott, Florida real estate developer. However, over half of the 91,000 signatures were rejected by election officials who deemed them invalid. After which time, she was able to meet the threshold in a second attempt late last year to get the measure on the ballot.

However, critics, including the ethics commission staff reportedly say the source of funding was not properly disclosed by Lisa Scott and her ballot committee. Lisa Scott’s attorney, Bruce Merrill, and the lawyer representing Shawn Scott, Alexis Fallon, contend that the Scotts have done nothing wrong, according to the Associated Press.