The grand jury investigation, first reported by WPRI-TV (Channel 12) is examining aspects of Mattiello’s 2016 campaign.

The state Board of Elections previously issued a warning to Mattiello and a Republican primary candidate, Shawna Lawton, who sent a campaign mailer supporting Mattiello in his tight general election race with GOP candidate Steve Frias. That was after the board found that Mattiello’s campaign team coordinated the mailer, after it was classified in a BOE filing as an independent expenditure.

Mattiello beat Frias in the November 2016 election, on the strength of mail ballots, by 85 votes.

Mattiello later conceded exceeding state campaign finance laws by about $72,000 during his 2016 race with Frias, but contended that that did not influence the outcome of the match-up. 

John Marion, executive director of the good government group Common Cause of Rhode Island, said he was pleased to learn of the grand jury investigation.

“Common Cause has never believed that that the Board of Elections came to the correct conclusion -- that Speaker Mattiello’s lack of personal involvement in the Shawna Lawton mailer allows him to large be held unaccountable in the matter,” Marion said in an interview. “We believe that the campaign finance laws in Rhode Island should be vigorously enforced and in this case, weren’t vigorously enforced by the Board of Elections.”

(The Elections Board, however, did refer the issue to the attorney general's office. "We went where the facts led us." Elections Board Chairman Steve Erickson said in a tweet. "chich meant a criminal referral. Which the AG is following up on. I am perplexed as to why that is not considered a good thing.")

Marion said the issue of ultimate responsibility for campaign activities is significant.

“Candidates have to be culpable for what’s done by their campaigns,” he said. “Otherwise, rogue campaign workers could do things in the names of campaigns that candidates could just disavow and there would be no penalty.”

Mattiello, a Democrat, first became speaker in 2014.

While the cost of the mailing ostensibly sent by Lawton was relatively small – about $2,000 – Marion said the amount of money is not the important factor.

“The importance here is that if illegal coordination is allowed to happen, that creates a back door through which money can flow into a campaign,” he said, “thus subverting the thousand dollar limit on contributions.”

After news broke Tuesday of the grand jury investigation, a spokeswoman for Mattiello’s campaign organization, Patti Doyle, issued this statement: “The Board of Elections resolved this issue for the campaign more than one year ago. We have no involvement in or knowledge of what was reported on earlier today.”

Apprised of Marion’s comments, Doyle said in a new statement, “We don't intend to look backwards at past campaigns but instead, remain focused on issues of import today. As we stated last night, the Board of Elections resolved this issue for the campaign over one year ago. We repeat - we have no knowledge of or involvement in this issue.”

Frias ran against Mattiello again in 2018, and lost by a wider margin than in 2016. Asked if he will run for rep against the speaker next year, Frias said, "Let's see what the grand jury reveals and what Mattiello does on the IGT no-bid deal."

Meanwhile, state Republican Chairwoman Sue Cienki praised Attorney General Peter Neronha -- who took office in January -- for triggering the probe of Mattiello.

"We are pleased that the attorney general has commenced a grand jury investigation into the illegal activities of House Speaker Mattiello’s campaign in 2016,” Cienki said in a statement. “We hope the grand jury investigation ends the cover up."

This story has been updated.