'I will destroy your life': Phoenix firefighter put on leave after history of DUI, threats

A Phoenix firefighter who was arrested last month after police said he sprayed foam into the plumbing system of a Peoria man's home and caused $25,000 worth of flood damage was accused of doing the same thing four years ago to another home.

A Phoenix spokesperson said the firefighter has been placed on administrative leave.

Peoria police arrested firefighter Greg Knauss in late February. Officers say Knauss cut into the roof of a townhome near 51st and Sweetwater avenues, vandalized the HVAC system, sprayed foam into the drainage and sewage pipes and sealed them shut. The sink, shower and toilet flooded, and the damage was so extensive, the foam reached into the city's sewer system, police said in court documents.

Knauss could not be reached for comment late Wednesday. His attorney declined comment.

Knauss, who has worked at the Phoenix Fire Department since 2006, has had a lengthy string of legal problems over the years. He was arrested on suspicion of extreme DUI, theft, forgery, public sexual indecency and urinating in public. He pleaded guilty to the extreme DUI in 2008. He entered a plea agreement to attempted theft and possession of a forgery device in 2012.

The city suspended him for one day after his DUI arrest and after he drove a fire truck on a suspended license, according to a city discipline notice.

In 2020, one of Knauss' neighbors sought a protective order against him, similarly accusing Knauss of spraying foam in his home sewage pipes and sealing them shut, along with poisoning his lemon tree and tinkering with the air conditioning unit.

Peoria police say a love triangle sparked the most recent foam incident in February.

The Peoria homeowner's girlfriend was the nanny to Knauss' children, and she and Knauss were "intimately involved," records say. When the Peoria homeowner threatened to tell Knauss' wife, Knauss texted the man: "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," police alleged in court records.

Maricopa County prosecutors charged Knauss on Feb. 29 in Maricopa County Superior Court with burglary in the second degree, a Class Four felony; two counts of criminal damage, Class Three felonies; and threatening or intimidating another person, a Class One misdemeanor.

Phoenix Fire Department spokesperson Ali Pardi said Knauss has been placed on administrative leave while human resources officials investigate. Pardi did not answer how long the leave would last, or whether it was unpaid.

Pardi also did not answer detailed questions from The Arizona Republic about Knauss' extensive legal history. Instead, she offered an emailed statement.

"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," Pardi said.

She did not elaborate.

Knauss suspended after DUI, reprimanded for driving fire truck on suspended license

Knauss was hired in Phoenix as a firefighter in 2006, then promoted to engineer in 2012. City records show he was a model employee, repeatedly praised in performance reviews.

"Your work ethic is a great example to all the guys at Station 1. Thanks again you are an amazing employee for the city of Phoenix. They are truly blessed to have you as an employee," supervisor Troy Hill wrote in 2018.

"His skillset is above standards," supervisor Jonathan Jacobs wrote in 2015. "He is smart, calm under pressure and hard working. He also provides great customer service to the community on all incidents. Greg is an exceptional employee and a great asset to the PFD in general. Greg is a pleasure to work with and has a great (rapport) with the crews."

But in 2008, Knauss was arrested on suspicion of extreme DUI and got his license suspended for a month. City documents show he then drove a city fire truck — a violation of city employee rules.

"Not acceptable," a city employee wrote in Knauss' file. "DUI was not listed in city driving history."

Knauss was suspended for a day and given a written reprimand. The letter warned him future violations could result in more severe discipline, including termination.

Guilty plea in 2012

In 2012, he was charged with theft and forgery after police said he tried to sell a stolen motorcycle. Knauss had purchased a foreclosed home, and a 2005 Titan sidewinder was in the yard, according to records filed in Maricopa County Superior Court. At the time, Knauss said he believed the purchase included the motorcycle and had applied for an abandoned title from the Motor Vehicle Department.

Knauss pleaded guilty to attempted theft and possession of a forgery device, considered Class Six undesignated felonies, the least serious. He was sentenced to two years' probation, which the courts terminated after seven months.

Phoenix employees are required to immediately disclose to their supervisors any law enforcement contacts, including DUIs, according to the employee and volunteer ethics handbook.

The handbook says misdemeanors or felony convictions "may be subject to discipline up to and including dismissal."

Pardi did not answer detailed questions about the 2012 incident, such as whether any disciplinary measures were taken.

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Similar pipe damage accusations in 2020

In 2020, Knauss wanted to build a carport, but he and his neighbor were arguing over the property line, according to documents filed at Encanto Justice Court. Then, the neighbor's lemon tree was poisoned, the air conditioner broke and the sewer line had been "blocked by some sort of spray foam or adhesive," the neighbor claimed.

When the neighbor confronted Knauss, Knauss said he had time and money, wasn't a dumb fireman, and that he held grudges and the neighbor hadn't seen anything yet, according to court records.

Since 2010, Knauss has registered a string of home investment companies with the Arizona Corporation Commission. His LinkedIn profile shows the company specialized in home remodel work. Peoria police said that's evidence he was capable of causing identical damage four years later.

In 2020, the Phoenix neighbor filed a police report. He also filed for an injunction against harassment against Knauss, similar to a protective order, at the Encanto Justice Court on Sept. 11 that year. The order was repealed after the court found inadequate evidence of Knauss' guilt.

In 2022, the neighbor filed a complaint against Knauss seeking $10,000 in reimbursements, but the Encanto Justice Court closed the case because Knauss was never served documents.

Knauss is due in court on March 15 to face charges in the Peoria case.

Taylor Seely covers Phoenix for The Arizona Republic / azcentral.com. Reach her at tseely@arizonarepublic.com or by phone at 480-476-6116.

This article originally appeared on Arizona Republic: Phoenix firefighter on leave after $25K spray foam vandalism claim