The family of five children who died when a fire ripped through their north Minneapolis duplex in February is preparing to sue the property’s owner for wrongful death.

A petition filed in Hennepin County District Court seeks to have a retired judge appointed as a trustee on behalf of the family, the first step in a potential wrongful-death suit. The family’s attorney, Jeffrey Sieben, said the suit will likely name property owner Paul Bertelson or his company Mission Inn Minnesota as a defendant.

The nighttime fire stunned the city, taking the lives of children 18 months to 8 years old. Their father, Troy Lewis, survived the blaze, as did two other children.

Sieben said that the suit could be filed by the end of the summer and that whether it will name other defendants depends on the outcome of a lengthy joint investigation.

“We don’t have any final conclusions now,” Sieben said Tuesday. “So I don’t know what the complaint’s going to look like, specifically.”

Bertelson deferred comment to Mission Inn Minnesota attorney Bill Moran, who said the investigation and analysis of the scene are ongoing.

“And so I’m really not at liberty to comment on what the intentions are of Mr. Lewis or his lawyers at this point because it is an ongoing process that we’re involved in,” he said.

Sieben said Lewis and other family members were not available for comment Tuesday.

Lewis has said the apartment lacked heat. While the Fire Department said the cause of the fire was undetermined, an incident report said it appeared to have started in the same area as a space heater Lewis had recently purchased.

Lewis said he had repeatedly alerted Mission Inn Minnesota to the heat problem. Bertelson countered that his company did not get calls about heat problems in the unit.

After the fire, conflicting statements emerged about heat sources in the apartment. Lewis told fire investigators that the space heater had been running for several days before the fire, according to the incident report, but then said in a news conference the space heater had been off during the day before the fire.

Lewis also said during the news conference that the oven — which he sometimes used to heat the apartment — had been on for a couple of hours when the fire started. He later said he turned it off at 9 p.m.

Sieben said a long list of stakeholders, including Mission Inn Minnesota, the family and insurance representatives, are jointly participating in the investigation. Experts are routinely being flown in from across the country to review evidence.

“We have been to the house several times,” Sieben said. “But I believe we’re done there. The items that were removed will be analyzed.”

That’s a lengthy process because of all the parties involved. “We have to coordinate all of those schedules, so anytime we open a bag of evidence, we are all there,” Sieben said.

While he said he expected the suit to be filed in late summer, he stressed that could change depending on the outcome of the investigation. “I just don’t know what we’re going to find.”

He said the team looking into the fire has not reached a conclusion about the finer points of what caused it, but know the area where it ignited.

The proposed trustee, retired judge Cara Lee Neville, has not yet been appointed. A hearing on that matter is scheduled for June 26 in Hennepin County District Court.

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