When a federal judge shot down a Trump administration policy of holding immigrants without bond last December, it seemed like a serious blow to the US president’s mass deportation effort.

Instead, a top justice department official insisted the ruling wasn’t binding, and the administration continued denying detainees around the country a chance for release.

By February, the district court judge in question, Sunshine Sykes, was fed up. Sykes accused the Trump administration of terrorizing immigrants and recklessly violating the law in its efforts to deport millions of people. She also said she regarded it as seeking “to erode any semblance of separation of powers”, adding that it could “only do so in a world where the constitution does not exist”.

Hardly isolated, the case illustrates a broader pattern by the US government’s executive branch, in Donald Trump’s second term, of defiance of decisions by the lower courts that are part of the judicial branch, with the tone set early by Trump and JD Vance, his vice-president. The US constitution’s creation of the three branches of government, with the legislative branch being the third, was intended to ensure checks and balances so that no branch had too much power.

The repeated refusal of Trump officials to follow court orders has been highlighted most notably in individual immigration cases.

But a review of hundreds of pages of court records by the Associated Press also shows an extraordinary record of violations in lawsuits over policy changes and other moves.

In the first 15 months since Trump returned to the White House, district court judges ruled the administration was violating an order in at least 31 lawsuits over a wide range of issues, including mass layoffs, deportations, spending cuts and immigration practices, the AP’s review found. That’s about one out of every eight lawsuits in which courts have at least temporarily blocked the administration’s actions.

The Republican administration’s power struggle with federal courts, which is testing basic tenets of US democracy, reflects an expansive view of executive authority that has also challenged the independence of federal agencies, a president’s ethical obligations and the US’s role in the international order.

The Trump administration violations in the 31 lawsuits are in addition to more than 250 instances of noncompliance that judges, some appointed by Democratic presidents, some by Republicans, have recently highlighted in individual immigration petitions – from failing to return property to keeping immigrants locked up past court-ordered release dates.

Legal scholars and former federal judges said they could recall at most a few violations of court rulings over the full four-year terms of other recent presidential administrations, including Trump’s first time in office before he lost to Joe Biden in the 2020 presidential election. They also noted previous administrations were generally apologetic when confronted by judges; the Trump administration’s justice department has been outright combative in some cases. Trump himself does not shy from vilifying judges, up to and including members of the US supreme court.

“What the court system is experiencing in the last year and a half is just qualitatively completely different from anything that’s preceded it,” said Ryan Goodman, a law professor at New York University who studies federal courts and is tracking litigation against the Trump administration.

Though Trump officials eventually backed down in about a third of the 31 lawsuits, legal experts say their treatment of court orders poses serious dangers.

“The federal government should be the institution most devoted to the rule of law in this country,” said David Super, a constitutional law scholar at Georgetown University. “When it ceases to feel itself bound, respect for the rule of law is likely to break down across the country.”

The White House’s aggressive policy moves have prompted a barrage of lawsuits – more than 700 and counting.

In October, the US district judge William Smith took little time to conclude that Department of Homeland Security (DHS) officials were flouting one of his orders. Smith had blocked them from making billions of dollars in disaster relief funding to states contingent on cooperation with the president’s immigration priorities.

The DHS responded by keeping the immigration requirement on some grants, but making it contingent on a higher court overriding Smith’s injunction. The judge called the move “ham-handed” and said the DHS was trying to “bully the states”.

In a case over the suspension of refugee admissions, the US district judge Jamal Whitehead accused the justice department last May of “hallucinating new text” in an appellate court order and “rewriting” it to achieve the government’s preferred outcome.

In four additional cases the AP reviewed, judges stopped short of a clear written finding of noncompliance but still criticized the administration’s response to their orders. Of the judges who have confirmed violations, 22 were appointed by Democratic presidents and seven by Republican presidents.

Former federal judges Jeremy Fogel and Liam O’Grady said judges are losing trust in the integrity of the Department of Justice.

That’s making them “more aggressive in accusing the government of bad faith”, said O’Grady, who along with Fogel is now part of the nonpartisan democracy group Keep Our Republic. Fogel said judges are also getting frustrated.

“They make orders and the orders don’t get complied with and then they have to inquire why the orders are not being complied with, and that’s where it gets very mushy and very political,” he said.

Guardian staff contributed reporting