Arizona firefighter charged with damaging second home

PHOENIX — Editor’s note: The video above is from a newscast on March 11.

A Phoenix firefighter, who has been charged with causing more than $25,000 worth of damage to a home in Peoria, has been arrested again and charged with damaging a home in Phoenix in 2020, according to court documents.  

Gregory Knauss, who has been a Phoenix firefighter for 17 years, was arrested on Feb. 27 and charged with damaging the Peoria home and threatening the homeowner through text messages. 

He is also accused of damaging a drain pipe, causing sewage to back up into a home in Phoenix and poisoning a tree in Sept. 2020. In total, the damage to the two homes cost more than $30,000, according to the new court documents. 

On March 12, just days after Knauss’ arrest in the Peoria case was announced, a man from Phoenix contacted Peoria police saying Knauss damaged his home in September of 2020 in a similar way to what happened in Peoria, the records say. 

The Phoenix man accused Knauss of coming onto his property, near the intersection of Thomas Road and Central Avenue, spraying foam into his drain pipe, which caused sewage to back up into his home through the shower, toilet and other water fixtures. The drain pipe ultimately had to be replaced. In total, the repairs cost $5,487, according to the new court documents. 

The victim also accused Knauss of poisoning a lemon tree and grass in his front yard. At the time, Phoenix police found a bottle of Pramitol 25E, a herbicide, in Knauss’ trash can, the records say. The Arizona Department of Agriculture confirmed the chemical was used around the tree and Knauss was issued a citation for illegal use of a pesticide.  

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Court documents say the Phoenix victim and Knauss were neighbors at the time of the damage and they had a dispute over a carport that Knauss planned to build that extended onto the victim’s property. The City of Phoenix ultimately did not let Knauss build the carport after zoning the victim’s property. The victim ended up getting an order of protection against Knauss after Knauss allegedly threatened him, saying the victim, “has not seen anything yet.” 

When the Phoenix victim spoke with Peoria police earlier this month, he showed a section of the old sewer pipe that still had the dried spray foam on it that matched the spray foam used in the Peoria incident. A tan Toyota Tacoma seen in videos of the Phoenix damage matched a truck that is currently registered to Knauss. 

Knauss was arrested again on March 21 in connection with the Phoenix damage and charged with third-degree burglary and three counts of criminal damage.  

Court documents also show Knauss has been arrested in the past for public sexual indecency, public urination, extreme DUI, selling stolen property, stealing a car and forgery. 

Knauss is expected to be back in court on April 5 for a status conference and his preliminary hearing for the Phoenix damage is scheduled for April 9.  

Knauss is also accused of drilling holes into the roof of a home and pumping spray foam into the plumbing and draining systems of the home, causing flooding and water damage in January.  

The new court documents also say Knauss damaged the HVAC unit on the roof of the home in Peoria. In total, the damages cost the homeowner and their HOA, Country Meadows Townhouses LLC, $25,684.  

The court documents say Knauss damaged the home in Peoria after getting into a dispute with the homeowner where the homeowner accused Knauss of being romantically involved with his girlfriend, who was the nanny of Knauss’ children, and telling Knauss’ wife. 

Knauss is also accused of sending threatening text messages to the victim, one of which said, “I know where you live and where you work. If you don’t think I will destroy your life, I don’t think you know who I am,” records say. 

Court documents say Knauss had access to the spray foam and tools to damage the home as he is the owner of a home remodeling business.  

RELATED: Phoenix firefighter charged with flooding West Valley home, doing $25K in damages

A witness reported seeing Knauss on the roof of the home after seeing his Phoenix Fire Department photo, and another witness had surveillance video footage showing him holding a can of spray foam, according to the spray documents. 

Peoria police arrested Knauss after executing a search warrant at his home in Phoenix, where they found items corroborating the witness’ statement and the surveillance video.  

He has been charged with second-degree burglary, criminal damage, harassment and threatening and intimidating.

Knauss was booked and fitted with an ankle monitor on Feb. 27.    

He is due back in court on May 2 for a pretrial conference. His trial is currently scheduled to begin on Aug. 8.  

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