President Donald Trump has appointed immigration hardliner Ken Cuccinelli to lead the United States Citizenship and Immigration Services, and in an email to staff Monday, laid out a direction for the agency that echoed much of the president’s restrictive immigration policies and rhetoric.

Cuccinelli’s hiring at the Department of Homeland Security agency is the latest change in leadership at the department as the Trump administration continues to search for ways to curb migration flows at the border.

“We must work hand in hand with our colleagues within DHS along with our other federal partners to address challenges to our legal immigration system and enforce existing immigration law. Together we will continue to work to stem the crisis at our southwest border,” Cuccinelli wrote to staff Monday morning in an email obtained by BuzzFeed News.

“We will also work to find long term solutions to close asylum loopholes that encourage many to make the dangerous journey into the United States so that those who truly need humanitarian protections and meet the criteria under the law receive them,” he said.

As a Virginia lawmaker in 2008, Cuccinelli sponsored a resolution calling for a rewrite of the Constitution to deny citizenship to Americans who were born to immigrants who crossed the border without authorization. Now, as director of USCIS, he is leading the agency in charge of assessing naturalization applications and administering the process, which includes interviews and oaths.

The high-profile leadership switches at the Department of Homeland Security began in early April, when then–acting director of Immigration and Customs Enforcement Ronald Vitiello had his nomination to lead the agency withdrawn by Trump. Soon after, then–DHS secretary Kirstjen Nielsen stepped down, followed by the departures of the acting deputy secretary and the chief of staff.

In the time since, acting heads have taken over at DHS and at ICE, US Customs and Border Protection, and, now, USCIS.

One DHS official said the announcement was dropped on employees suddenly and could be distracting during an already tumultuous time.

“My concern is with employees and their morale,” the official said.

The agency, previously under the leadership of L. Francis Cissna, whom Trump forced to resign, had been considering moves to institute a fee for asylum applications, extend the time asylum-seekers needed to wait to obtain work permits, and ban asylum for those traveling through Mexico to the US.

Former USCIS officials said the email sent by Cuccinelli — who previously served as Virginia’s attorney general and unsuccessfully ran for governor of the state — was concerning.

The agency has long been known as focused on providing services to immigrants, evaluating visa, work authorization, and naturalization applications.

Under the Trump administration, it has made a restrictive turn, focused more on enforcement, former officials say. Now, with Cuccinelli in charge, it appeared the agency was set on an even tougher course.

“Everything in that email suggests he is more interested in enforcement than in services, which is the agency’s mission,” said Ur Jaddou, former chief counsel at the agency. “The growing list of constant policy changes at USCIS has dramatically slowed the agency’s core mission. Case processing time has surged and backlogs are growing.”

Other DHS officials said they were troubled about the way in which Cuccinelli was brought on board -- as an acting director.

"I’m concerned about the effect on the agency, both in morale and in direction this will take us, and I’m further concerned about the legality of the appointment,” one DHS official said.

Steve Vladeck, a professor at the University of Texas School of Law, said the appointment wasn’t consistent with the Federal Vacancies Reform Act. The 1998 statute allows the president to select certain senior officials to fill fill cabinet and agency positions. At USCIS, Cuccinelli’s official title, as of Monday, is principal deputy director.

“I think it's not flatly in violation of the plain text of the FVRA, but it is certainly inconsistent with its spirit,” he said. Cucinelli has long odds of being confirmed by the Senate, where he has faced criticism from Senate Majority Leader Mitch McConnell.

"The statute is designed to prevent using this kind of maneuver to help a nominee's nomination," Vladeck said. "It didn't occur to Congress to also prevent it when the President wants to use it to install someone on an acting basis with no chance of Senate confirmation."

Under the statute, the only way for Cuccinelli to have become eligible to be selected to lead the agency in an interim fashion, was to be deemed a "first assistant." Anne Joseph O'Connell, a professor at Stanford Law School, said that no court has ever ruled on whether someone can be named “first assistant” after a position has been vacated, like in Cuccinelli’s case.

To that end, the selection of Cuccinelli could lead to a legal challenge that would settle that debate, she said. An individual who has been denied a visa or immigration benefit could have standing to sue over the appointment.

“It seems like a claim that a party would want to bring, given the ambiguity in the act,” O'Connell said, before adding that she believed it was likely a legal maneuver. “I think it is technically legal though not desirable.”