Stationed Overseas, but Solving Crimes in New York City

“How did you get here so fast?”

Those were James Currie’s first words when Sgt. Edward Lee of the New York Police Department’s Intelligence Bureau walked into a room to interview him at Suvarnabhumi Airport in Bangkok on the morning of Aug. 8.

Mr. Currie, a 37-year-old subway cleaner from the Bronx, had left New York City from John F. Kennedy Airport on a 2:19 p.m. flight to Abu Dhabi two days earlier, a day after his infant son, Mason Saldana, had been discovered floating lifeless in the East River. Detectives in New York had gathered evidence suggesting Mr. Currie had left Mason in the river, where he was seen by tourists on Aug. 5.

Sergeant Lee’s quick appearance in Thailand was no coincidence. Since 2013, he had been stationed in Singapore as one of 14 New York detectives posted overseas as part of a longstanding counterterrorism program created by Raymond W. Kelly, the former police commissioner, and David Cohen, the former chief of the Intelligence Bureau.

Since its inception in 2003, the International Liaison Program has been funded by private donations from the New York City Police Foundation, a nonprofit. Mr. Kelly’s successors at Police Headquarters, William J. Bratton and James P. O’Neill, both continued to assign detectives abroad, and expanded the number of overseas posts.

“In a post-9/11 world, we wanted to learn as much as we could about terrorism,” said Thomas P. Galati, the department’s chief of intelligence. Overseas detectives gather information on terrorist attacks to send back to New York City, including tactics, names of people suspected of terrorism, their potential connections to the five boroughs and even technical details about homemade bombs.

But Chief Galati said the mission of the program had shifted over time, and these days his officers were investigating other crimes. “As it evolved from terrorism, we started to see more and more criminal cases coming up,” Chief Galati said. He cited an instance where some of the $800,000 worth of watches taken in a December 2017 gunpoint robbery from the A. Lange & Söhne boutique on Madison Avenue were tracked down to a pawnshop in Amman, Jordan. “The world is a small place,” Chief Galati said.

There are 14 detectives embedded with law enforcement agencies in Holland, France, Canada, the Dominican Republic, Spain, Jordan, the United Arab Emirates, Qatar, Singapore, Israel and Australia. In the United States, the program recently expanded to California, with a detective assigned to Los Angeles.

The intelligence bureau’s domestic operations outside of the city have generated controversy previously. The bureau drew fire for monitoring Muslim organizations in other Northeast states and for sending undercover officers to an activist summit in New Orleans and to Ferguson, Mo., during the civil disturbances in 2014.

Other law enforcement and intelligence agencies, particularly the F.B.I. and C.I.A., have opposed the department’s overseas deployment. Mr. Kelly was criticized for sharing information about terror attacks in London in 2005 and Mumbai in 2008. Federal officials have also complained about the police “freelancing” their own terrorism investigations.

Critics say the Police Department’s liaison program has expanded its focus to justify its ongoing existence without answering deeper questions about the necessity of the initiative.

“It’s a completely wide-open program established with no oversight at all,” said Mike German, a former F.B.I. agent and a fellow at the Brennan Center for Justice.

Critics have also raised questions about the influence of the police foundation’s donors over the department’s policies, and the absence of government oversight for the nonprofit that was founded in 1971. For instance, in 2015, the online news organization The Intercept reported that the United Arab Emirates had donated $1 million to the police foundation to aid unspecified “investigations.” A New York police detective has been stationed with the Abu Dhabi police since 2009.

Susan Birnbaum, the president of the police foundation, said the donation from the Emirati government was benign and was not part of a quid pro quo. She also said the U.A.E. was the only foreign government that had donated money to the organization.

Mr. German, the former F.B.I. agent, said the donors should be disclosed. “What does a foreign government think that it’s getting in exchange for its money?” Mr. German said. “How can New Yorkers be confident that information gathered here in New York City isn’t being shared with foreign governments inappropriately?”

Chief Galati said the department carefully scrutinized each intelligence request from an overseas law enforcement agency to make “certain that it’s legally sound in America.” In the past, the department has rejected inquiries from foreign governments about political dissidents.

Whatever larger policy questions exist about the international liaison program, in the case of Mr. Currie, the network proved critical to his capture.

Detectives in Manhattan have said they were sure Mr. Currie was involved with his son’s death. The boy’s mother, Julia DeJesus Saldana, had given Mason to his father on Saturday afternoon for a two-day visit under a custody agreement, but Mr. Currie never dropped the 7-month-old off at his day care center on Monday, the police said.

The intelligence bureau at Police Headquarters, with help from the United States Immigration and Customs Enforcement agency, ran checks on Mr. Currie with Customs and Border Protection and learned he was flying to Bangkok, with a connection in Abu Dhabi.

Lt. John Miedreich, the commander of the international liaison program, contacted Detective Andy Kamarchevakul, the department’s liaison in Abu Dhabi, and sent him to meet Mr. Currie at the gate. But by the time the detective arrived at the airport, Mr. Currie had caught an earlier flight and was on his way to Thailand.

The lieutenant then called the department’s detective at Interpol’s headquarters in Lyon, France, Alain Di Nicola, and had him request a “blue notice,” an international alert asking the police in other countries for help locating someone wanted for questioning.

Lieutenant Miedreich then contacted Sergeant Lee in Singapore, where it was midnight, and ordered him to catch the next flight to Bangkok. In the meantime, Mr. Currie was detained at about 5 a.m. as he got off the flight from Abu Dhabi. The Royal Thai Police had seen Interpol’s blue notice and were holding him.

Three hours later, Sergeant Lee walked into a detention room at the airport and interviewed Mr. Currie. The sergeant, who had started his career as a beat cop in Queens, had a good working relationship with the Thai authorities. On Aug. 10, Mr. Currie was escorted back to New York and stood before a judge in Manhattan Criminal Court, charged with concealment of a corpse. He has pleaded not guilty, and denied any role in the boy’s death in a jailhouse interview with The Daily News. The city’s medical examiner has not yet determined what caused Mason’s death.

“Gathering as much information as you can and cultivating relationships with foreign police departments, it’s not really something anyone trains you on,” Sergeant Lee said. “There’s nothing specific that’s in the patrol guide.”