New York Attorney General Eric Schneiderman has pursued a total of 100 legal or administration actions against President Trump and congressional Republicans since Mr. Trump entered office, The New York Times reported Tuesday.

A lawsuit announced recently by Mr. Schneiderman in response to the Federal Communication Commission’s decision to repeal Obama-era net neutrality protections marked the 100th time his office has taken aim at the Trump administration and Republicans in Congress, The Times reported.

“We try and protect New Yorkers from those who would do them harm,” said Mr. Schneiderman, the Empire State’s attorney general since 2011. “The biggest threat to New Yorkers right now is the federal government, so we’re responding to it.”

The FCC voted along party lines Dec. 14 to repeal net neutrality protections, slashing rules prohibiting Internet Service Providers from prioritizing content and subsequently triggering legal threats from attorneys general throughout the country, Mr. Schneiderman included.

“This is not just an attack on the future of our internet. It’s an attack on all New Yorkers, and on the integrity of every American’s voice in government — and we will fight back,” Mr. Schneiderman vowed following the FCC’s 3-2 vote.

While several states have announced plans to sue over the FCC’s net neutrality vote, Democrats “don’t have a stronger or smarter ally” than Mr. Schneiderman, said Massachusetts Attorney General Maura Healey.

Mr. Schneiderman “stepped into a chasm where today’s ideological divisions create a lot of room for litigation,” Ms. Healey told The Times.

Prior to announcing plans to sue the FCC this month, Mr. Schneiderman’s office initiated dozens of other actions against the Trump administration and congressional Republicans, including challenges mounted against all three of the president’s proposed travel bans and Mr. Trump’s rolling back of environmental regulations, among other policies, The Times reported.

“I did anticipate that the administration was going to be aggressively regressive,” Mr. Schneiderman said. “I did not anticipate the volume that he was going to start pumping out so quickly. These guys were generating lots of trouble very quickly.”

The White House referred The Times to the Department of Justice when reached for comment.

“The federal court system is not a substitute for the legislative process,” DOJ spokesman Devin M. O’Malley told the newspaper. “The Department of Justice will continue to defend the president’s constitutional and statutory authority to issue executive orders aimed at securing our borders, protecting U.S. workers, promoting free speech and religious liberty, among many other lawful actions.”

Mr. Schneiderman previously led inquiries into Mr. Trump’s businesses dealings prior to his election, including a fraud case against Trump University that ended with the president-elect agreeing last November to pay a $25 million settlement.