Activists who are worried that the NYPD’s long-standing focus on petty crimes like turnstile jumping could newly expose immigrants to deportation under President Donald Trump picketed City Hall on Thursday.

The demonstrators decried the city’s overwhelmingly liberal politicians for continuing to back the NYPD philosophy of broken windows — targeting petty offenses to forestall major crimes. The city credits the approach, begun two decades ago under a Republican mayor, with driving down crime since the 1990s.

Karina Garcia of the Act Now to Stop War & End Racism Coalition faulted Mayor Bill de Blasio for distancing NYPD practices from the fallout of a Trump executive order intensifying immigration enforcement.

“You’re asking us to separate the act of deportation from what is pushing immigrants into the deportation machine, and that happens because of local policies that you control,” said Garcia, 31, of Elmhurst, Queens.

Trump’s order, signed Jan. 25, applies both to “removable aliens” — any noncitizen: those convicted and those merely charged.

The activists say it’s not enough that in 2014 the mayor signed council legislation booting the U.S. Immigration and Customs Enforcement agency from city jails and barred the correction and police departments from honoring federal requests in all but the most serious circumstances.

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According to the latest figures covering about a year, the city turned over two detainees: one who was convicted of second-degree gang assault, the other for second-degree assault. Citing the convicts’ privacy, the mayor’s office declined to release those detainees’ names, specifics of their crimes or home countries. Before the law de Blasio signed, between Oct. 1, 2013, and Sept. 30, 2014, the city jails transferred 2,061 people to the immigration agency.

Trump has threatened to cut off federal funds to “sanctuary jurisdictions” like New York. The NYPD alone gets more than $150 million in such money.

Over the past week, de Blasio and City Council Speaker Melissa Mark-Viverito, both Democrats, have demurred when asked about the prospect that low-level NYPD arrests could be grist for deportation, saying it’s too early or speculative to know what Trump will do.

Alma Magaña, a Legal Aid lawyer who spoke at the rally, said the immigration agency uses NYPD arrestees’ fingerprints and other information to track down immigrants.

“Every time police are out there continuing policing with the broken window policing that they’ve been doing,” she said, “every time they arrest someone who has no status, who’s overstated their status, or whose status has expired, those individuals are going to be picked up by ICE.”