DACA recipients – often called DREAMers – are facing a new nightmare. According to the Trump administration, Immigration and Customs Enforcement (ICE) officers may use the information these people gave the government as a means of gaining temporary protection to, instead, find and deport them.

In deportation proceedings, the government must prove that the person they want deported is in the U.S. illegally. That can sometimes be tough. DACA recipients – nearly 800,000 of them – gave the Department of Homeland Security information proving they are undocumented so they could get relief from the threat of deportation. They also gave the government information about where they live, work, and go to school. As soon as Donald Trump was elected, immigrants’ rights activists started asking what his administration would do with that information.

In a memo, the Department of Homeland Security answered this question. And its statement – full of wordy legalese – made clear that Immigration and Customs Enforcement officers will be able to use DACA recipients’ personal information to deport them.

“Information provided to USCIS in DACA requests will not be proactively provided to ICE and CBP for the purpose of immigration enforcement proceedings, unless the requestor meets the criteria for the issuance of a Notice To Appear or a referral to ICE under the criteria set forth in USCIS’ Notice to Appear guidance,” said the statement.

In other words, USCIS (United States Citizenship and Immigration Services, the agency which handles DACA) won’t proactively give immigration enforcement officers a list with the names and addresses of all DACA recipients. But if ICE officers ask for it, the agency will provide it.

“They’re saying we will not give your information unless ICE tells USCIS they need it to deport you, which basically means we’ll give your information out whenever ICE says it’s necessary to deport you,” said Leon Fresco, an immigration attorney who represents many DACA recipients. “That’s the point.”

Shortly after the administration announced the decision to rescind DACA following a six month buffer period, the White House issued a set of talking points to its supporters that reiterated this.

“Information provided to USCIS in DACA requests will not be proactively provided to ICE and CBP for the purpose of immigration enforcement proceedings,” read the White House talking points memo, which was obtained by The Daily Beast. “With that said, it can be utilized for such proceedings when appropriate.”

In practical terms, Fresco said, this means that any DACA recipient who gets arrested by police will be vulnerable to deportation. That’s because police alert a host of federal agencies, including ICE, when they make arrests. ICE officers will then be able to ask USCIS if people who were arrested have received DACA—and, thus, are in the U.S. illegally.

The end result will be that a good chunk of the 800,000 or so DACA recipients will simply recede from public view entirely.

“If people go back in the shadows and don’t have any interactions with law enforcement of any kind, their likelihood of being removed is not high,” Fresco said.

“The key is doing everything you can to avoid interactions with the police,” he added. “That’s pretty much all you can do at this point.”