New York City Mayor Bill de Blasio speaks at the Harlem Youth Town Hall, Friday, July 17, 2020, in New York. Photo: Frank Franklin II/AP

Mayor Bill de Blasio and City Hall's top lawyer on Wednesday roundly rejected threats by President Donald Trump to send federal agents to quell protests in U.S. cities, as the New York City Bar Association likened the forces to an unlawful "standing army."

In public comments, de Blasio and corporation counsel Jim Johnson vowed to sue the Trump administration if federal agents were deployed in New York City, where protesters have gathered in mass demonstrations following the police killing of George Floyd in Minneapolis.

The federal government, through the Department of Homeland Security, has in recent weeks deployed security forces to Portland, Oregon, with the stated intention of protecting federal property there. However, reporting and video from the protests have shown the often-unidentified agents detaining demonstrators and placing them in unmarked cars.

Trump himself has remarked on the need to "dominate" the protests in U.S. cities, and Chad Wolf, the acting secretary of homeland security, said in a Fox News interview that he had the authority to "proactively arrest" people. Trump, meanwhile, has defended the actions as necessary to restore law and order and threatened to take similar steps in other large cities, like New York, Chicago and Philadelphia.

The statements have sparked outrage from Democratic politicians and local leaders, who have said they would refuse to accept the presence of federal law enforcement in their cities.

On Wednesday, de Blasio said that similar actions by the federal government in New York would be unnecessary and "counterproductive."

"I want to be very, very clear that we will not allow this to happen in our city. And this could only make things worse," de Blasio said, according to a transcript of the remarks.

"We don't take something like this lying down," he said. "We will not be intimidated. And if we see these federal officers on our streets, then we will see the Trump administration in court to stop it from happening."

In a letter Wednesday to Wolf and Attorney General William Barr, de Blasio added that the use of uniformed federal forces would only work to undermine the city's existing relationship agreements with U.S. Marshals and other agents to protect federal buildings.

Johnson, speaking alongside de Blasio at a press conference Wednesday morning, said that Trump was "inviting chaos to an already difficult situation" and that any unwelcome incursions by the federal government would be met with coordinated legal challenges from local officials.

"The constitution gives the state and the city quite clear responsibility for local law enforcement," Johnson said enforcement. "New York City is the safest big city in the United States. We will continue to keep it that way. And we will challenge this in court. I've been in touch with my counterparts in other cities and we are prepared and preparing to attack this in a coordinated way."

In its own statement, the City Bar called the actions in Portland a "threat to all Americans" and urged attorneys to fight back against what it said violated the U.S. Constitution.

"The use of federal agents in this way is equivalent to the standing army that was feared by our founders and cannot be accepted as 'normal' but rather as an action contrary to our history, tradition and democratic norms," the City Bar said.

"Lawyers everywhere have a special obligation to insist that our government comply with the laws and Constitution that embody our nation's deepest values, and to make clear, in words and responsible action, that those federal officials who authorize, direct or carry out such violent and unlawful actions must be held accountable under the law."

The mayor's comments came as he is under increased pressure over his handling of the protests in New York City, as well as his controversial decision to forcibly remove protesters from an encampment outside of City Hall early Wednesday morning. Protesters there had been camped out for over a month demanding that the city cut $1 billion from the New York City Police Department's $6 billion budget and reinvest the funds into social programs.

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