Brian Wallace, the former state representative from South Boston, has become something of a connoisseur of campaign finance investigations.

That can happen when your political career is derailed by an indictment for campaign finance violations — as Wallace’s was in 2012.

So he was surprised when he recently read about the deal Brian Joyce just cut with state ethics officials. Joyce, a state senator from Milton, had been accused by the state Republican Party of a litany of campaign finance irregularities. Following an investigation by the Office of Campaign and Political Finance, the issue was resolved with an agreement for Joyce to pay $4,617 in restitution and promise to behave better in the future.

“I couldn’t believe it,’’ Wallace said. “I was destroyed for less than he did.’’

Though the relative scale of their misdeeds is debatable, Joyce has reason to be pleased with the outcome of his case. He was not required to admit to legal wrongdoing, though he freely admits — in retrospect — that his handling of his campaign cash has left much to be desired.

Joyce, a Beacon Hill fixture, has been the subject of multiple recent ethics probes, and he probably isn’t done being investigated. In a lengthy telephone interview Thursday, he insisted that he had never violated the state’s frankly lax ethical standards and predicted full exoneration. But he was contrite as well, admitting that he had, at times, been guilty of lousy judgment.

At the center of the most recent investigation was a graduation party Joyce threw for his son. Of the $5,200 cost of the party, $3,367 was paid by his campaign finance committee. Joyce has agreed to pay back the money billed to his committee, which will be donated to the Massachusetts Hospital School, a Canton-based facility for people with special needs.

Why would anyone think that a party for as senator’s family member can be charged to a campaign committee?

“I took steps to separate personal expenses from what I thought were legitimate expenses,’’ Joyce told me. “Was I wrong legally? No. But it was just a bad judgment call on my part.’’

Joyce said he was relying on the legal standard that allows a politician to use campaign funds for anything “that enhances a candidate's political future.’’ Since virtually anything could be said to enhance one’s political future, it is a notoriously porous statute.

Still, this is not Joyce’s first dust-up with the ethics police. He was recently cleared of wrongdoing by the State Ethics Commission in a long-running battle over his purchase of designer sunglasses for his Senate colleagues, possibly for less than their full market value. Just this month, allegations have surfaced of a dubious arrangement in which he received free dry cleaning for years — in exchange, he maintains, for legal work. Governor Charlie Baker, among others, has called for an investigation into that deal.

Joyce said he assumes the matter will be investigated.

He said the ethical cloud he has labored under for the past year has been difficult on his family and others close to him.

“I’ve said that in retrospect I used bad judgment, but I expect — eventually — to be exonerated and to get on with my life and help my family heal, and to represent the people I’m paid to represent,’’ Joyce said.

By comparison, Wallace was indicted for failing to properly document $51,000 in campaign expenditures and $6,345 in contributions, in a case that was ultimately resolved in fines and pre-trial probation. He narrowly escaped jail time.

Now 65, he works part time at the Norfolk County House of Correction, writing books on the side. He marvels, bitterly, at his former colleague’s penchant for escaping consequences.

Joyce insists he is simply the victim of sloppy record-keeping and the occasional poor decision. But as the questions about his ethics keep coming, those explanations will be put to the test.

Adrian Walker is a Globe columnist. He can be reached at walker@globe.com.