New Jersey joined California and 14 other states in a lawsuit challenging President Donald Trump’s declaration of a national emergency to get access to billion of dollars in military funding to erect a wall at the southern border, Attorney General Gurbir Grewal said Monday.

In a statement, Grewal echoed criticisms from fellow Democrats who have said Trump is engaging in an unconstitutional abuse of his powers by using the emergency declaration to gain access to billions of dollars that Congress refused to authorize.

“The real national emergency is a president who refuses to adhere to the rule of law,” Grewal said. “In its effort to cater to a select few on the right, this administration is trampling on our Constitution and circumventing the will of Congress.”

The announcement of New Jersey's participation in the lawsuit, which was filed Monday evening, came hours after protesters, bearing signs and under cold gray skies, gathered in towns and cities across New Jersey to condemn the president's move.

Dozens arrived outside the Peter Rodino Federal Building in Newark just before noon and began to chant, "We are going to beat beat back the Trump attack" as a few drivers honked their horns in solidarity. A similar scene played out in Red Bank, where a crowd arrived at Riverside Gardens Park to show discontent over the president's move, which he announced Friday.

"Trump carried out an undemocratic power grab because he is directly threatened by our democracy,'' Nedia Morsy of Make the Road New Jersey, an immigrant activist group, said to the crowd in Newark, which numbered more than 100. "In our democracy, all people could have their voices heard and their perspectives shared."

Other protests were scheduled Monday in Morristown, Princeton, Collingswood and Toms River in New Jersey, as well as in Philadelphia and New York City and in cities in Texas and California.

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The Trump administration face a wave of legal challenges from those who disagree with the move.

California's attorney general promised to "definitely and imminently" challenge the emergency declaration in court. California was joined Monday by New Jersey, Connecticut, Colorado, Delaware, Hawaii, Illinois, Maine, Maryland, Michigan, Minnesota, Nevada, New Mexico, New York, Oregon and Virginia as plaintiffs in the suit, filed in U.S. District Court for the Northern District of California.

The states claim in the suit that the emergency declaration was "unlawful" and "unconstitutional," and they want the courts to prevent Trump from diverting federal funds toward construction of the wall.

Read the entire lawsuit at the end of this story

Rep. Tom Malinowski, a New Jersey Democrat, said he would co-sponsor a resolution to revoke the emergency.

"If the House passes it, under the National Emergencies Act the Senate will have 15 days to vote up or down,'' he wrote on Twitter. "This isn't about building or stopping the wall; it's about defending the Constitution."

Legislators from Trump's own Republican Party have also expressed opposition to the move.

U.S. Sen. Marco Rubio of Florida said the action appears to violate the Constitution and that he fears the precedent it sets for future occupants of the White House.

"Today's national emergency is border security. But a future president may use this exact same tactic to impose the Green New Deal," Rubio said in a statement.

Supporters of the wall and of the emergency declaration said the president has the authority and responsibility to protect the country's borders.

Rep. Matt Gaetz, a Republican from Florida, wrote on Twitter over the weekend that crimes that occur at the border are preventable.

"If we have a physical barrier at the border, where the cartels and traffickers can’t bring people here illegally, we can 100% stop those crimes. #BuildTheWall,'' he wrote.

The emergency declaration will allow for the use of $8 billion to build 234 miles of wall, the White House said. The amount is much larger than the $5.7 billion Trump demanded before he signed off on a bipartisan spending bill last week to avoid another government shutdown. That bill allocates $1.38 billion for 55 miles of barriers.

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The rallies held on Monday, Presidents Day, were described by some as "non-violent rapid response events" and were arranged by several organizations. The Newark rally was organized by Make the Road New Jersey, and the one in Morristown by Wind of the Spirit.

In Newark, where a giant inflatable chicken with a Trump-style hairdo towered over protesters, demonstrators observed a moment of silence for three migrant children who fell ill and later died after crossing the border. They called for defunding U.S. Immigration and Customs Enforcement and U.S. Customs and Border Protection, the agencies in charge of enforcing the Trump administration's hard-line immigration policies.

"I'm here today to denounce President Trump's attacks against our immigrant communities, against all of our communities and against our democracy," said Alberta Jimenez of Passaic, a member of Make the Road New Jersey. "We are here today to say enough: ICE is killing our children, they are separating our families, they are detaining our parents and our neighbors."

Many of the protesters carried homemade signs expressing their thoughts about the wall. Some of the signs read "Impeach Trump," "Stop the Deportation Machine" and "Trump is the Emergency."

The Rev. Robin Tanner of the Beacon Unitarian Universalist Congregation in Summit said she visited the border south of San Diego in December with other faith leaders. There is no crisis, she said.

"This is completely fabricated. When we were down there, we saw a handful of folks waiting for asylum applications to be processed,'' she said. "There is a real moral crisis in this country. There are 140 million people living in poverty in the United States, and that's a crisis; we should be talking about that."

'This country is built on immigrants'

Laura Porter arrived at the Red Bank rally in a light-green gown and matching face paint, and held a sign bearing an excerpt from Emma Lazarus’ poem "The New Colossus."

“Je m'appelle la dame liberté,” she said — French for “My name is Lady Liberty.”

Porter said she drove to Red Bank because there wasn’t a protest closer to her home in Jackson, which isn’t surprising, considering that the township voted overwhelmingly for Trump in 2016.

“I do believe that this country is built on immigrants,” Porter said.

She has been researching her family’s roots and found that her son has an ancestor who came to the United States as a Hessian soldier in the Revolutionary War era and was allowed to stay.

Jim Keady, an activist who has run against Rep. Chris Smith, a Republican, noted that it was a fitting way to spend Presidents Day. A protester nearby showed off a poster that read: “Not my president’s day.”

“We know that the current president that is occupying the White House is violating the very Constitution upon which this nation was founded,” Keady said, drawing cheers.

Rita Dentino, director of the immigrant rights group Casa Freehold, blames the fencing that already exists as well as the country’s enforcement policies for the deaths of immigrants who have crossed the border illegally, many of them fleeing gang violence in Central America.

“Every single bit of wall makes a refugee’s journey more dangerous,” she said. “Refugees — people fleeing for their lives — must choose a perilous, dangerous path to get here, and they die. They die in our southern deserts.”

“The wall we already have is no good,” Dentino said. “More wall is worse.”

During the protest, a man yelled “Build the wall!” as he drove past the park in his pickup truck. Protesters booed him.

Red Bank is among the New Jersey municipalities that have adopted a “Fair and Welcoming Community” resolution. Red Bank’s resolution, approved in April 2017, does not limit how local law enforcement and federal immigration agents interact, but rather expresses support of all borough residents, regardless of their immigration status.