It is a classic practice memorialized in countless television cop dramas: an enterprising detective offers a cigarette or soda to a suspect in a police interrogation room.

But a federal class-action lawsuit filed Monday night in the Southern District of New York accused the NYPD, working with the city medical examiner’s office, of unconstitutionally using that practice to collect possible suspects' DNA from cigarette butts, empty cans or bottles left in interrogation rooms. The suit, filed by the Legal Aid Society, tells the story of a 12-year-old brought in for questioning who was given a soda from McDonald’s that an officer, clad in rubber gloves, later carefully collected to search for DNA fragments, according to court filings.

Phil Desgranges, supervising attorney for Legal Aid, said this means that everyone, including children, can potentially become “permanent suspects,” as each individual's unique biological data could be stored in a suspect index and compared to evidence in future crimes, regardless of whether that person was charged with a crime.

“If the NYPD wanted to search someone’s cell phone, if they wanted to search your home, they would have to get a warrant or court order to do so,” Desgranges said. “But here, they’re getting this ability to effectively search your genetic material perpetually without any authorization from a court, and without any knowledge of the person whose DNA is being taken.”

The Legal Aid Society filed the class-action lawsuit against the city, along with top NYPD and medical examiner officials, on behalf of the more than 30,000 people with DNA in the suspect index as of the filing. Lawyers said they hoped to get the DNA profiles expunged from the index and stop the NYPD and medical examiner from taking and holding DNA in perpetuity.

It is unclear if other police departments around the country collect DNA from people who have not yet been convicted or even charged with crimes. Attorneys from Legal Aid said they were unaware of this practice elsewhere.

The NYPD defended the practice as being in the service of justice to accurately identify perpetrators, build cases for investigators, and “bring closure to victims and their families,” according to Sgt. Edward Riley, an NYPD spokesman who commented to Gothamist via email on Monday.

“Behind every time the NYPD collects DNA from a suspect in a criminal investigation, there is a crime victim who is suffering and seeking justice,” Riley said.

He did not respond to questions about specific allegations in the suit.

“The NYPD’s investigations and tactics, including the collection of DNA, are guided by what is authorized by the law, the wealth of case law from the courts, and the best practices of the law enforcement community,” he said.

The Office of the Chief Medical Examiner has said that it will not analyze DNA unless there’s criminal evidence for it to be compared to. On Monday, a spokesperson released a statement in response to the filing of the suit saying “the local DNA database complies with all applicable laws and is managed and used in accordance with the highest scientific standards set by independent accrediting bodies that have regularly reapproved the existence of the database.”

Shakira Leslie, 26, was a named plaintiff in the case. She was arrested in 2019 after a gun was found in a vehicle she and four others occupied during a police stop. She said she was later held at a precinct for 16 hours, where she endured an intense interrogation.

Twelve hours went by before officers asked her if she wanted a bottle of water, she said.

“I was starving, I was dehydrated, I was everything there was … I was definitely going to drink that water by the time they asked me,” she said in an interview.

But that water bottle was how her DNA was collected, her attorneys said. Ultimately, her DNA was compared with DNA on the weapon. Without a match, she was exonerated and all charges were dismissed, according to the lawsuit.

But she was still shocked to learn that her DNA was even collected in the first place, she said.

“I’m an innocent person,” she said. “My DNA shouldn’t have to be there.”

Leslie, who has never been convicted of a crime, was 24 when the incident happened. And years later, she said, she still feels on edge around sirens and police.

“I have no trust,” she said. “Give people the option. Let people give the option to give their consent. Don’t treat an innocent person like a criminal. And that’s what they did to me.”

In recent years, officials removed thousands of DNA samples from the suspect database, mostly because they weren’t convicted or suspected of any crimes, according to the medical examiner's office. And as of this month, there were 31,826 samples stored, NYPD data showed.

Desgranges said "the trap is set" oftentimes before suspects even enter the interrogation room, where detectives have already wiped down the room's tabletops with Clorox to remove anyone else's strands of hair or remnants of skin containing DNA. It is not until after the suspect enters the room when an offer for a drink, for example, is made, the supervising attorney said.

A video obtained by Legal Aid showed one officer pointing to a water bottle, which a suspect took a drink from. After he was handcuffed and led out of the room, an officer returned to collect the bottle. Another video showed a suspect being offered a Newport cigarette. The ashtray was seen later being emptied into an evidence bag.

Suspects are forbidden from taking their trash, like water bottles and soda cans, out of the room, the lawsuit alleged. A copy of the NYPD Detective Guide gives instructions on how to secretly collect the DNA, according to the lawsuit, and the guide neither mandates nor recommends consent.

The NYPD did not respond to a question about whether officers continue this practice.

Unlike state and federal DNA databases, New York City’s is not subject to legislative oversight and restrictions on whose DNA can be stored. The New York State database only collects the DNA of those who have been convicted, as per state law.

An NYPD official told the City Council in February 2020 that it would gather demographic information on those in the DNA suspect database. But the NYPD did not provide such information when Gothamist asked on Monday. The Office of the Chief Medical Examiner said it doesn’t maintain such information.

“We need to reign in this lawless and unregulated taking and indexing of primarily Black and Latinx people’s DNA,” Desgranges said, referring to the fact that most people arrested by the NYPD are not white. “I’m sure wealthy, white New Yorkers would not want to hand over their DNA to the government, and there should not be one policy for primarily poor, Black, Latinx folks and a different policy for people who are much more privileged.”

This story has been updated.