FORT COLLINS, Colo. — Two sets of tenants in Pueblo allege they were poisoned by carbon monoxide in the same apartment unit, and their attorney believes the landlord is to blame.

Carbon monoxide is an odorless, colorless gas that can be deadly.

Carbon monoxide detectors are required in dwelling units with fuel-fired appliances or an attached garage or parking structure, as these are potential sources of carbon monoxide.

Carbon monoxide deprives the brain of oxygen, and at high levels or with prolonged exposure, it causes irreversible brain damage.

Attorney Sam Cannon represents two Pueblo brothers who filed a lawsuit last year claiming their landlord’s negligence left them with permanent brain damage after carbon monoxide poisoning in their apartment.

► Watch Colette Bordelon's report in the player below:

CO tenants say they suffered from permanent brain damage from carbon monoxide in their apartment

“There are two primary clear laws that we often run into: The first is the carbon monoxide detector law, which says that in any rental unit, the landlord has to ensure there are functional carbon monoxide detectors when a new tenant moves in. Second, under the sort of landlord-tenant laws, we call it the warranty of habitability, landlords have a responsibility to make sure their heat and hot water systems are installed to code, that they're in good working order," explained Cannon.

The complaint was filed in Pueblo County Court on April 7 against C & S Grand Investments, LLC, and its managing member, Jason Scott Berrier.

According to the lawsuit, the two brothers were hospitalized with life-threatening carbon monoxide poisoning in April 2024 from a malfunctioning furnace, which the landlord allegedly tried to fix himself without a required license.

The property is located at 2805 N. Grand Avenue in Pueblo.

“It was this case of a furnace that had been installed improperly and had been serviced by someone who wasn't licensed, wasn't qualified, and a landlord who hadn't placed carbon monoxide detectors in the unit," said Cannon. "It very fortunately did not result in any deaths, but it's about as close as you can come.”

Cannon said his office was contacted by another tenant of that same apartment complex in Pueblo, who said she believed she also experienced carbon monoxide poisoning. His office filed a counterclaim in response to the landlord's lawsuit against the tenant for unpaid rent.

“The tenant told us that the same thing had happened to her — that the furnace was still only being worked on by an unqualified technician, and that she was also exposed to carbon monoxide in the same unit," said Cannon.

Cannon said he is actively working on a handful of carbon monoxide-related cases, which he said are rare. He believes the rental market in Colorado is one reason why he has seen so many similar cases.

“People are unable to afford their own homes. People who are in unstable housing situations are at a disadvantage when dealing with their landlords, and that allows landlords to get away with, you know, not repairing furnaces, not checking carbon monoxide detectors, and that sort of thing," said Cannon.

The tenant in the second case, Rachelle Clementi, sent the following statement to Denver7:

“Clients want, obviously, they want to be made whole to the extent that's even possible, but more than that, they really want other people to know that this can happen," said Cannon. "The more people know, the more they can protect themselves and make sure this doesn't happen to them either.”

Denver7 reached out to the defendant named in this case and did not receive a response before publication.