Over the past two years, Mayor Eric Adams has made no secret of his frustrations with New York City’s migrant crisis. But after President-elect Donald J. Trump’s victory, the mayor’s criticism has taken a sharper turn to the right.

Mr. Adams, a Democrat, declared last week that migrants accused of crimes should not be entitled to due process under the Constitution.

Over the weekend, he said for the first time that he was exploring whether he had the power to alter so-called sanctuary laws and allow the city to collaborate more closely with federal authorities to detain “dangerous” immigrants — potentially using an executive order to bypass the Democratic-led City Council.

And later this week, he is scheduled to meet with Thomas Homan, Mr. Trump’s “border czar,” to hear how the administration’s immigration plans would affect New York City and to explore common ground between the city and the Trump administration.

“In the last few weeks, he’s obviously sharpened his rhetoric, sort of moving closer toward the Trump rhetoric,” said George Arzt, a longtime political and communications consultant. “He was like this on law-and-order rhetoric, and so now he’s sort of melded the law-and-order with migrants.”

The question is why.

Mr. Adams, a former police officer who made crime the bedrock of his campaign, has insisted that his stance on immigration, like much of his overall mayoral platform, is driven by his concern for public safety.