Gregory Nisbet listens to a statement from Lisa Leconte-Mazziotti, mother of Nicole Finlay, who died in a fire in a building owned by Nisbet in 2014, in court in Portland in this 2016 BDN file photo.

Maine’s top court is set hear the appeal of a Portland landlord convicted of a misdemeanor for his role in the state’s deadliest house fire in decades.

A lawyer for Gregory Nisbet is scheduled to argue Tuesday that the Maine Supreme Judicial Court should overturn the landlord’s fire code violation — the only conviction to come out of his high-profile, 2016 trial for manslaughter.

The case was an unusual instance of a landlord being held criminally liable for deaths in an accidental fire at their property. It saw Nisbet acquitted of six counts of manslaughter and several misdemeanor charges related to the 2014 fire that killed six people at his Noyes Street duplex.

[Landlord not guilty of manslaughter in Maine’s deadliest house fire in decades]

Nisbet was sentenced to serve 90 days in jail for his conviction but has remained free as a series of legal maneuvers culminating in his appeal have wended through the courts. In February, he paid civil settlements to the families of the six people killed in the fire, and to one survivor.

A year after his conviction, Nisbet’s lawyers quit because he’d stopped paying them and the landlord said the proceedings have left him “indigent.”

Nonetheless, Nisbet has found a lawyer to carry on his appeal. Luke Rioux, of Portland, will make his client’s case to the state’s top court during a Tuesday afternoon hearing at the Capital Judicial Center in Augusta.

[Two years after the deadly Portland fire, two little girls learn the truth of how their father died]

A judge convicted Nisbet of a fire code violation because the windows on the third floor of his building were too small to offer a second means of escape. Three of the people who died in the fire were found on that floor, while two others were found elsewhere in the home and one died later in the hospital.

The fire at 20 Noyes St. was kindled by a stray cigarette butt, which ignited a chair and couch on the front porch of the building, investigators found. After the house burned, the city found numerous building, safety and fire code violations at another of Nisbet’s properties on Dartmouth street.

In court filings, Rioux argued that the state fire code is too vague to be enforced without violating someone’s due process rights. He also rehashed an issue a judge rejected after the landlord’s original lawyers raised it following the trial — that prosecutors allegedly broke the rules of evidence disclosure.

Chief Justice Leigh Saufley recused herself from the case without explanation.

Follow the Bangor Daily News on Facebook for the latest Maine news.