The officials allege that the firm illegally reimbursed lawyers and their spouses for up to $175,000 in campaign contributions to state candidates and causes. If the case is referred to the attorney general, it would mark the first time state officials sought criminal penalties for straw donations. And commentators have pointed out that the allegations, if proven, would make this one of the largest reimbursement cases in US history - if not the largest. In a letter to the law firm’s partners and their spouses last month, Office of Campaign and Political Finance director Michael Sullivan said he intended to present to the attorney general evidence of violations of the state’s campaign finance law from 2013 to 2016.

Campaign contribution charges

Mr Sullivan outlined that the partners had violated Section 10, which prohibits individuals from making a campaign contribution in any name other than his own and except his own, nor in any manner intended to disguise the true origin of the contributions. The allegations, if proven, would make this one of the largest reimbursement cases in US history, if not the largest both in terms of the total amount of money involved and the length of time over which the scheme was carried out, Brett Kappel, an election law expert at Akerman LLP, a Washington, DC law firm was reported as saying in the Boston Globe.

Deny wrongdoing

However, Thornton Law Firm’s lawyers have insisted the reimbursement system was legal, since the lawyers were being repaid out of their equity in the firm. Thornton is a small firm not counted among the 100 largest law firms in Massachusetts and yet was the 11th ranked law firm nationally for political contributions in 2014.

Top Democrats hand back cash

The move has seen top Democrats such as Hillary Clinton and Elizabeth Warren return more than $1 million in donations from the firm. Most returned monies went to the US Treasury rather than directly back to Thornton.