The Mayor said the City has received several reports which show a pattern of ICE agents claiming to be local police while carrying out enforcement activity.
In the letter, sent to interim ICE Director Tony Pham and ICE New York Field Operations Director Thomas Decker, de Blasio said the reports indicate "ICE officers often identify themselves as "police" or "detectives" and state that they are conducting an investigation."
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The Mayor said the reports allege agents have even stated they were from specific police precincts or squads, such as the "narcotics squad" and even arranged to meet an individual at a police precinct.
"These types of activities jeopardize the willingness and comfort of immigrant NewYorkers in interacting with the NYPD on crucial matters involving public safety and local law enforcement," de Blasio said. "The NYPD already conducts regular community outreach to immigrant community members to educate the public about our confidentiality policies for all victims and witnesses, regardless of immigration status. ICE actions that exacerbate confusion about NYPD's work and relationship to immigration enforcement are counterproductive to these efforts."
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De Blasio's letter marked the latest flashpoint in a long-simmering conflict over New York City's so-called sanctuary policies.
Earlier this year, ICE took the city to court after the de Blasio administration balked at "immigration subpoenas" it received from the government, seeking information about a handful of inmates wanted for deportation. The city ultimately provided limited details about the inmates, even as it derided the subpoenas as a "political stunt."
The action reflected ICE's mounting frustration with jurisdictions that do not honor deportation "detainers" or provide any details about defendants going in and out of local custody.
De Blasio added in his letter that "New York City remains the safest big city in America in large part because of NYPD's work to ensure that victims and witnesses of crime feel safe coming forward."
Information from the Associated Press was used in this report.
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