Rep. John Lawn, a Watertown Democrat who co-chairs the Legislature’s Health Care Financing Committee, was penalized by campaign finance regulators last month for “inadequate” record keeping, filing finance reports late, and multiple instances of receiving excess contributions.

The lawmaker purged $14,000 in donations, appointed a new campaign treasurer, and personally paid $500 to the state for the cost of reviewing his records to resolve the violations of state law, according to the Office of Campaign and Political Finance.

In a letter to Lawn, OCPF Director William Campbell said campaign finance regulators “determined that no further action” was warranted because “appropriate remedial actions have taken place.”

“However, further instances of noncompliance with the campaign finance law may result in referral to the attorney general in accordance with Section 3 of the campaign finance law or legal proceedings that could prevent your name from appearing on a state or local ballot in Massachusetts,” Campbell said.

Lawn, who won reelection in November after running unopposed and is the only state lawmaker to be cited by campaign finance regulators so far this year, said he is “grateful” to campaign finance regulators for “bringing these matters to my attention.”

“Once I was made aware, I immediately took the necessary steps to rectify them, including hiring a professional campaign treasurer. Ultimately, it is my responsibility to ensure accurate and final reports to OCPF. Going forward, given the steps we have taken, I am confident the campaign committee will not face any of these issues in the future,” Lawn said in a statement to the Herald.

The campaign finance law requires politicians’ campaign committees to file finance reports that accurately reflect contributions and expenditures on time. The reports must include information about who donated to a candidate or elected official and when the money was received.

In the March 25 missive to Lawn, Campbell said contributor information for roughly $104,500 that the Watertown Democrat received between January 2023 and August 2024 was “not timely filed.”

“In addition to the committee’s inadequate record keeping procedures, the late filing of reports exacerbated the issue of receiving excess contributions,” Campbell said in a letter. “Had reports been prepared and filed in a timely manner, the aggregate limits would have been clearer to the committee and the excess contributions could have been avoided.”

Lawn brought in excess contributions in 2022, 2023, and 2024, including from political action committees, lobbyists, and individual donors.

Campaign finance regulators said Lawn received contributions from political action committees that exceeded the state-mandated yearly limit in December 2022 by $1,750, in 2023 by $6,950, and in 2024 by $2,600.

“To resolve these matters, the committee purged the sum of $11,300 to the commonwealth,” Campbell said in the letter.

Lawn received $1,200 in excess contributions from five lobbyists, according to regulators. State law limits the amount a single lobbyist can contribute to a candidate or elected official to $200 in a calendar year. Lawn gave the state $1,200 to resolve the matter.

State regulators also said that Lawn received and deposited a $500 bank check even though his campaign committee “was not able to determine the source of this contribution and incorrectly attributed the receipt to a PAC.”

“The campaign finance law requires committees to keep accounts, including the full name and address of all contributors to a committee regardless of the amount,” Campbell said in his letter to Lawn. “Anonymous contributions may not be accepted … To resolve this matter, the committee purged the sum of $500 to the commonwealth.”

Lawn’s campaign committee was dinged for filing late reports clarifying $57,500 in spending, documents detailing sub-vendors, and failure to “keep and preserve detailed accounts, vouchers, and receipts for all contributions received, expenditures made, and any other campaign finance activity.”

“The delay in filing required reports frustrated the public’s interest in accurate and timely disclosure of campaign finance activity during the relevant periods,” Campbell wrote in the letter.