The United States Justice Department is suing the state of New Jersey and Gov. Phil Murphy over policies that keep law enforcement officers from fully cooperating with immigration officials.

Federal officials say that New Jersey’s “Immigrant Trust Directive” implemented by Attorney General Gurbir Grewal violates the U.S. Constitution and obstructs federal law enforcement efforts.

Murphy defended the policy on Tuesday and said that he would fight the lawsuit.

“We will defend our position vigorously,” he said.

Federal prosecutors say that the Constitution “does not allow New Jersey to obstruct the enforcement of federal laws … the directive is therefore, invalid.

"This is cold-bloodedly about the safety and security of all the 9 million folks who call this great state home. And it concerns me when the Trump administration would take a step like that,” Murphy said.

Murphy and Grewal say that the directive is in place to protect all New Jersey residents, regardless of immigration status, and that it allows people who may be living in the country illegally to feel that they can contact New Jersey police without fear of being deported.

"It has increased trust and cooperation between the State Police, local police and immigrant communities - it has,” says immigration attorney Regis Fernandez.

Fernandez says that if the Immigration Trust Directive is altered to discontinued, thousands of immigrants would likely feel less safe.

“The immigrant communities would likely go back into the shadows and would feel like they could not – they would just be apprehensive about approaching the police,” he says.

The Justice Department says that in the first year that the directive was in force Immigration and Customs Enforcement agents apprehended 16% fewer undocumented defendants.

Grewal called the lawsuit an election-year stunt.

"The majority of immigrants don't commit crimes. But there is, you know, there's a small group of people in every group that don't get the message,” says Fernandez.

The lawsuit does not challenge parts of the directive which deal with inmates in county and state jail facilities. The resolution to this likely to come in federal court in the coming weeks or months.