Phoenix firefighter accused of damaging home had prior criminal history | Crime Files

We are learning more about a man who is accused of causing thousands of dollars in damage to a home.

The man, who is with the Phoenix Fire Department, reportedly had run-ins with law enforcement prior to this incident.

Here are the details.

Who's the suspect?

Gregory Knauss

The suspect has been identified as 40-year-old Gregory Knauss.

Why was he arrested?

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Knauss, according to our initial report, was arrested for allegedly causing more than $25,000 of damage to a town home during what was reported to be a romantic dispute.

According to detectives, a witness spotted Knauss on the roof of a town home in Peoria on Jan. 23. They say Knauss clogged the home's plumbing with spray foam and vandalized the air conditioning unit. Court documents also accuse Knauss of making large perforations in the roof with an unknown tool. 

The incident reportedly caused substantial damage to the interior and exterior of the home.

"During the day of [Jan. 23, 2024], weather conditions generated large amounts of rain, which caused substantial water damage to the interior and exterior of the home as a direct result of [Knauss] clogging the plumbing and drainage pipes with spray foam, and making large perforations in the roof with an unknown tool," read a portion of the documents. "Spray foam placed into the plumbing and residential sewer drain was so extensive, it created a barrier that reached into the City of Peoria sewer system from the exterior access point, where the cap to the pipe was also adhered with an unknown sealant, causing responding plumes to be unable to access the drain without significant time and effort."

As for the HVAC system, investigators say internal and external wiring and/or components were damaged.

Prosecutors note that Knauss was involved in an apparent romantic dispute in 2023, with Knauss accused of being intimately involved with the girlfriend of the person who lived at the home where the vandalism incident happened. The girlfriend was, at the time, the nanny of Knauss's children, and Knauss's wife was notified of it.

Knauss allegedly sent threatening messages to the woman's boyfriend, one of which, as listed in court documents, reads as follows:

"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."

Investigators also noted that Knauss is the owner of a business that specializes in residential modeling, which "supports [Knauss] having sophisticated knowledge of residential structural, electrical, and plumbing tradecraft that was used to facilitate the significant amount of damage to the residence in the manners observed."

Knauss, according to investigators, was arrested on the morning of Feb. 27 by Peoria Police.

You mentioned Knauss had prior run-ins with law enforcement?

Court documents we obtained for Knauss shows the suspect had prior arrests for public sexual indecency, urinating in public, extreme DI, trafficking stolen property, theft of means of transportation, and forgery.

The documents also show that Knauss was convicted of extreme DUI, trafficking stolen property, theft of means of transportation, and forgery.

We have learned that in one of the incidents, Knauss was fined less than $1,000 and served about a year of unsupervised probation after he was arrested for trying to sell a stolen motorcycle to an undercover cop.

What is Knauss being accused of this time?

Court documents state that Knauss is accused of committing six offenses: 2nd degree burglary, criminal damage - defacement, criminal damage - tampering, criminal damage - tampering with utilities, harassment, and making a threat.

A judge released Knauss on his own recognizance. According to Cornell Law School's Legal Information Institute, this term is used when a person is released from custody without bail, and the defendant makes a written promise that he will appear in court when required to do so.

The same judge, however, also ruled that Knauss cannot be released from custody until electronic monitoring equipment has been installed, and he will also be subjected to a number of restrictions, including a curfew.

Is Knauss still with Phoenix Fire?

Phoenix Fire officials have confirmed that Knauss is still employed by the department, but is on administrative leave amid an investigation into this latest arrest.

We also reached out to Phoenix Fire officials to ask about his prior convictions, and we received a statement that reads:

"The Phoenix Fire Department is aware of previous allegations and issues related to Mr. Knauss. Each issue was investigated and managed consistent with our process and when warranted the appropriate level of discipline was given. Regarding the most recent allegations, we are actively investigating and managing through the process."