Brentwood police dog bit second woman in head, records reveal

WARNING: Viewer discretion advised. This story includes disturbing video and pictures. 

A Brentwood police K-9 bit a woman in the head, she says, as she hid in an attic crawlspace one year before the same dog ripped the scalp off a shoplifter hiding in bushes –  an incident that drew widespread media attention, KTVU has learned.

The German Shepard named "Marco" and its handler made national headlines last month when video of the second gruesome attack in February 2020 was made public by KTVU. The injured woman in that case, who was permanently disfigured, filed a federal civil rights lawsuit last month against the city of Brentwood and its police department. 

But revelations that Marco bit another woman in the head, who also appeared to be hiding unarmed in a prone position, raises more questions about how the Brentwood Police Department deploys its K-9 unit. The officer wrote in a police report that he thought the woman hit her head on a nail.

GRAPHIC WARNING: Brentwood police dog bites woman hiding in crawlspace

The two documented head bites by this particular K-9 comes as police departments around the nation have faced more scrutiny about how they use dogs in dealing with suspects. A 2020 investigation by The Marshall Project found that law enforcement agencies often use dogs on people who are unarmed with little accountability. 

The latest incident to come to light involving Marco happened on Jan. 30, 2019, and like the second case, was captured on a police body worn camera. The video shows then 33-year-old Christine Niederer of Brentwood bleeding from the head, saying she was bitten by the dog inside the cramped crawlspace in her home on the 400 block of Edgefield Place. The video does not show the dog biting the woman. 

"I’m losing a lot of blood," Niederer, who’s visibly bleeding from her head, says in the video. "The dog bit me. He bit my head."

Pictures of Niederer’s wounds show bloody punctures on her hands and arms along with a large jagged gash on the top of her head that doctors later stitched closed.

"It was appalling," Niederer's mother, Jamie Ramey, said in an interview with KTVU on Friday. "My daughter is ruined. My daughter has PTSD because of it." 

WARNING: These photographs are disturbing.  


Christine Niederer was wounded on the head after she said she was bitten by a police K-9 that later bit off parts of another woman's scalp. 

KTVU obtained a police report of the incident through a public records request. It’s written by Officer Ryan Rezentes, who is Marco’s handler and was also the officer involved in the 2020 biting of Tamilka Bates, who had been hiding in bushes after she and her friends shoplifted an estimated $10,000 in cosmetics from a nearby Ulta beauty store. 

In the report, Rezentes said that when he came upon Marco and Niederer inside the crawlspace, he witnessed the dog biting the woman’s hand and could see blood on her head, which he "believed was from striking it on a beam or from an exposed nail from the roof."

In an interview, Ramey said the officer's explanation was "ridiculous," and said it's undeniable that the dog sunk its teeth into the top of her daughter's head.

"You don’t get 11 stitches in two places due to a nail," she said. 

RELATED: Brentwood police dog rips off young woman's scalp

The mother said her daughter has a history of mental illness and brushes with the law that include felony convictions. She said that doesn't excuse the wounds her daughter suffered from the dog. 

In a statement Friday, city officials told KTVU the incident was reviewed by the Brentwood Police Use of Force Committee which found the deployment of the K-9 to be within policy and law under the circumstances.  

Rezentes wrote in his report that he’s been Marco’s certified handler since 2015. The K-9, Rezentes wrote, is trained "while on a search to locate a suspect and bite them until I remove him from the bite."

The episode began around 7:40 p.m. that night when police got a call about a dispute. They immediately recognized the address and had prior encounters with Niederer, who was on probation at the time for felony charges that included a weapon. 

Rezentes wrote that when he came to the scene, he learned that Niederer had been in a fight with her significant other, who was moving out. Niederer had threatened her girlfriend and used a folding table to push her out of the garage, striking her in the shin, the officer wrote.

The woman's name was redacted from the police report. She declined medical attention at the scene. 

WARNING: These photographs are disturbing.  

Split screen

Since she was on probation, Niederer was subject to a search without a warrant. The officers drew their guns ordered everyone inside the home out, and began looking for Niederer.

During their search, they discover an opening in the ceiling inside the garage leading to the crawlspace. The officers order Niederer to come out before Rezentes said, "Christine, if you're in the attic I’m going to get my K-9 and send him up there. He’s going to bite you. Come out now."

He then hoists the dog into the dark hole, and it disappears.

Rezentes later explained why he used the dog in his report, saying Niederer’s prior felony involved a weapon, that he believed she was under the influence of alcohol, and that she has restraining order against her by the neighbors. He added that he didn’t know if she was armed at the time.

"If Niederer was cornered with nowhere else to flee to, it may activate her ‘fight’ or ‘flight’ natural response to a situation," he wrote. "Thus, leading to a struggle between her or officers, posing a danger to myself or my covering officers."

After several minutes of not hearing from the dog inside the crawlspace, Rezentes went in after it and started crawling on the exposed roof joists. 

That’s when he said he heard a woman scream and knew the dog "was on a bite." Rezentes located "Marco" and got him to release his bite from Niederer’s hand. The officers then lowered her through an opening above a bedroom closet.

"I didn’t hurt anybody," Niederer says in the video. "I didn’t do anything." She later said, "I did not deserve this. I did not do anything wrong."

Paramedics later arrived at the home and treated Niederer before she was taken to a hospital and then to Martinez jail. She was later charged with misdemeanor counts of injuring a spouse, resisting arrest and probation violation.

Records show that Niederer is currently incarcerated at Central California Women’s Facility in Chowchilla. 

Evan Sernoffsky is an investigative reporter for KTVU. Email Evan at and follow him on Twitter @EvanSernoffsky