When Suffolk County police responded to a 911 call in Long Island the morning of Jan. 17, they found Michael Valva, a New York City police officer, in the basement of his home performing CPR on his son, Thomas. Valva told police the 8-year-old fell in the driveway while waiting for his school bus and lost consciousness.

Thomas was taken to a hospital, where he was pronounced dead. Investigators would later say that when Thomas arrived, his body temperature was just 76 degrees. His father’s story, meanwhile, was quickly unraveling, police say.

On Friday, Suffolk County police charged Valva, 40, and his fiancee, Angela Pollina, 42, with second-degree murder and accused them of engaging in conduct that “created a grave risk of death to this child,” Suffolk County Police Commissioner Geraldine Hart announced in a news conference the same day.

“Thomas Valva was subjected to freezing temperatures in the home’s unheated garage overnight, when the outside temperature was 19 degrees,” Hart said. The medical examiner said hypothermia was a major factor in Thomas’s death. Hart said investigators quickly determined that injuries to the boy’s face and head were “inconsistent” with the timing of events and the narrative that Valva gave Suffolk police.

Investigators later found audio and video from the family’s home surveillance system, which the parents used to monitor Thomas, his two brothers and Pollina’s three daughters. The Suffolk County district attorney’s office did not immediately respond to requests for comment, but prosecutors told the New York Times that investigators found video taken two nights before Thomas died that shows him and one of his brothers shivering on the garage floor without a mattress, pillows or covers.

Valva and Pollina have pleaded not guilty but remain in jail after being held without bail.

“Right now [Pollina] is maintaining her innocence,” her attorney, Matt Tuohy, told The Washington Post on Sunday. “It’s going to be a long road. There’s a lot of evidence that hasn’t been brought out.”

An attorney for Valva did not immediately respond to requests for comment Sunday.

Five other children were in the home with Thomas: his 6-year-old and 10-year-old brothers and Pollina’s 6-year-old daughter and 11-year-old twin girls. The surviving children were taken out of the family home on an emergency basis and placed in a “safe environment,” Hart said.

“We are still investigating the extent of the abuse and if it extended to all the children,” Hart said. “These arrests are not the end of the investigation.”

Hart said officials were called to the home last year for a welfare check, but no one was home when they arrived. She declined to comment on previous allegations that Valva was abusing the children.

Valva’s ex-wife, Justyna Zubko-Valva, had apparently alleged for years that her children were being abused by their father. It’s not clear why Zubko-Valva lost custody of her three children in 2017; court records show she filed for divorce from Valva last year.

A Twitter account identified as Zubko-Valva’s by the New York Post appears to document the mother’s attempts to get help since at least January 2018.

Zubko-Valva has said Thomas and one of her other sons have autism. A tweet from Jan. 8, 2018, reads, “Father and his girlfriend are brainwashing my special needs children and teaching them hatred towards their mommy. Parental alienation = children abuse. My children have a right to love their mommy. Taking away that right is a crime.”

The account contains dozens of posts, videos and photos of the children, as well as what appears to be reports in which a school psychologist and special education teacher documented concerns that two of the boys were coming to school hungry and dirty and that Valva and his fiancee “do not understand the depth” of their disabilities.

“There are so many people responsible for this tragedy,” Zubko-Valva told the New York Post after her estranged husband’s arrest. “The institutions that are supposed to protect the children protect the abusers.”

Suffolk Social Services Commissioner Frances Pierre told News12 in Long Island that petitions against the family alleging child neglect were filed in 2018, and that safeguards, including court-ordered home supervision for a year, were put in place.

After Thomas’s death, Hart said investigators believe he and his 10-year-old brother were punished with food deprivation and forced to stay in the frigid garage.

Detective Annette Shelton, a spokeswoman with the New York Police Department confirmed that Valva, who was assigned to the transit division, had been suspended from his job without pay.

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