When former President Donald Trump threatened a wave of mass deportations in the summer of 2019, U.S. Immigration and Customs Enforcement mobilized to deliver.

But those raids turned out to be more hype than reality — in part because of opposition from local law enforcement leaders, including Harris County, Texas, Sheriff Ed Gonzalez, who runs one of the country's biggest jails in Houston.

"I do not support #ICERaids that threaten to deport millions of undocumented immigrants, the vast majority of whom do not represent a threat to the U.S.," Gonzalez tweeted at the time. "The focus should always be on clear & immediate safety threats. Not others who are not threats."

Sheriff opposed aggressive tactics for dealing with undocumented immigrants

ICE became the public face of the Trump administration's hard-line immigration policies. Now the Biden administration wants to overhaul the agency, and it's turning to Gonzalez to lead the effort.

His nomination hearing on Thursday before a Senate committee comes at a moment of turmoil inside ICE. Many officers felt empowered under Trump to arrest anyone living in the country illegally. Now those officers complain they are the ones being handcuffed as the Biden administration tries to limit the agency's focus to what it considers serious threats to public safety and recent border crossers.

Gonzalez has tangled publicly with ICE more than once. The Houston native spent 18 years with the Houston Police Department before serving on the City Council. When he first ran for sheriff, Gonzalez pledged to take Harris County, which includes Houston, out of a controversial cooperation agreement with ICE.

"I want to use the resources that we have to address real crimes that are happening in our community," he said in an interview with Houston Public Media in 2016. Gonzalez also said he opposed aggressive tactics that other sheriffs had adopted to arrest undocumented immigrants.

"It leads to the potential for racial profiling. It potentially splits families," Gonzalez said. "It doesn't make us any safer because in many ways it diminishes the trust and respect that could occur between law enforcement and the community."

Some ICE officers are unhappy with changes under the Biden administration

But immigration hard-liners argue the public was safer when ICE agents were encouraged to arrest anyone they encountered who was in the country illegally. And they warn that morale at the agency has plummeted.

"The message that I'm hearing from officers in the field is that they are very discouraged," said Jon Feere, who was chief of staff at ICE during the Trump administration. He's now with the Center for Immigration Studies in Washington, which advocates for lower levels of immigration.

Feere said many ICE officers are unhappy about strict new guidelines that limit arrests, but they're afraid to speak out for fear of losing their jobs.

"They feel that they are sitting around looking for something to do," Feere said in an interview. "They know that there are plenty of individuals that they could arrest and could remove, and they're basically not being allowed to; the guidelines are very narrow."

The Biden administration and its allies counter that it's typical for policies to shift from one administration to the next.

"These employees at ICE get whiplash every time there's a change in administration or direction," said Sarah Saldaña, the last ICE director to be confirmed by the Senate. Saldaña served in the job during the second term of the Obama administration when the agency adopted similar enforcement priorities.

"That was we're going to focus on true threats," she told NPR. "Who is the greatest threat to the American people? Is that a family that comes over and is trying to find a place in the world where it's safe? Or is it a drug smuggler who runs an international operation?"

The next ICE chief will have to address the growing number of asylum-seekers

Arrests at ICE are down sharply since President Biden took office. But the number of immigrants in custody is rising — from a low of fewer than 14,000 earlier this year to more than 27,000 last week. Many of them are migrants who recently crossed the border to seek asylum and have no criminal record. The incoming head of ICE will face immediate pressure from all sides about whether to hold them in detention or not.

"I hope he gets confirmed. I think he will bring a degree of compassion and greater humanity to the agency," said Mana Yegani, an immigration lawyer in Houston, where she's followed Gonzalez's career.

Gonzalez is widely credited with changing the culture at the Harris County Sheriff's Office. Yegani said she's hopeful he can do the same at ICE.

"He's very low key. He's not on the news or the media or, you know, showboating of any sort," Yegani told NPR. "But he does care. And he does get the job done, in my experience."

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