Mayor de Blasio is promising to protect all the thousands of undocumented immigrants who have signed up for a municipal ID. That could mean the city will destroy the applications for the program. But already, two GOP lawmakers are going to court to try to prevent that from happening. Our Courtney Gross has more from Staten Island.

It's an application with a wealth of information.

They're documents these members of the State Assembly want to get their hands on.

"This city, this state and this country for that matter should never be put in a position where they are less safe for some political agenda," said Staten Island Assemblyman Ron Castorina.

In the shadow of this Staten Island courthouse, these Republican lawmakers say they're suing the city officials to block them from potentially destroying records collected during its municipal ID program.

In 2014, the program was designed to give New Yorkers who might not be able to get a state ID an opportunity to have some official identification. It meant some undocumented immigrants would have an ID for the first time.

Now, with a Trump administration and the potential threat of deportations, the city is considering destroying all of those records.

"We made very clear there would never be a situation where it would lead to their deportation," Mayor de Blasio said. "We are going to keep that pledge. And it's also part of our law, stated very clearly in the legislation. So we will follow through on that."

He is right about that. The law says in December of 2016 the city can reassess how much record retention it needs going forward.

The city has not made a final decision on the issue.

Still, these lawmakers want to get a judge to weigh in before it is too late.

"My issue is protecting the citizens and the residents that we represent," said Staten Island Assemblywoman Nicole Milliotakis. "It's the primary concern here. It's the reason why documents should not be destroyed."

When IDNYC was first announced, some advocates warned the program actually created a database for anyone looking for undocumented immigrants to deport.

"New York City said to its population, 'Trust us with these documents and we will protect you. We will protect the documents and we will protect your safety,'" said Johanna Miller, with the New York Civil Liberties Union. "And now they really have to make good on that promise."

The city has no plans to discontinue the municipal ID program. In fact, they are encouraging people to sign up.