Thomas D. Homan, deputy director for U.S. Immigration and Customs Enforcement, is being criticized by the union that represents ICE officers. (Jabin Botsford/The Washington Post)

Immigration and Customs Enforcement chief Thomas D. Homan and a vocal labor union that represents part of the agency's workforce are both big fans of President Trump's tough deportation policies. But they are increasingly at odds with each other.

Tensions spilled over in November when Trump nominated Homan to serve in the role permanently. The National ICE Council went public with allegations that the agency is "grossly mismanaged" and urged Trump to investigate. An ICE spokeswoman called the union's claims "baseless" and said agency morale has increased nationwide since Homan took the helm in January.

Seeking to quell the controversy, Trump reached out to union president Chris Crane to set up a meeting. But the White House also says it steadfastly supports Homan, who is awaiting a Senate confirmation hearing and has backing from Republicans in Congress.

"The president nominated Tom Homan for his decades of experience and steadfast commitment to enforcing the law," said Raj Shah, a White House spokesman. "He has earned the strong support of the rank-and-file ICE officers and will make an outstanding director."

The dispute pits two of Trump's loyal supporters against each other — the union that endorsed him for president and the top ICE official who defends his hard-line views. It is erupting as the White House is urging Congress to significantly expand the agency.

Critics dismiss the union's complaints as part of a long-running power struggle and say the allegations are either unsubstantiated or amount to isolated incidents in the sprawling federal agency. But union leaders, who represent 6,000 employees, say they are frustrated by what they call a failure by Homan and other top managers to stem misconduct in an agency that has little public oversight.

Christopher Shanahan, who retired as a deportation field office director in late 2016, said that the union is notoriously difficult and that Homan is widely admired. Homan "stands up for people when they deserve to be stood up for," Shanahan said. "He can be tough when he needs to be tough."

Union officials and other critics point to an array of issues nationwide. An internal ICE review last year found that employees at Newark's deportation office complained that managers offered promotions and other assignments based on "personal friendships and sexual relationships." In San Diego, union leaders say employees have filed more than 20 discrimination complaints since fiscal 2015. Felix Luciano, an ICE officer and president of the union's local in San Diego, said Homan "has turned a blind eye to report after report of problems" in that office.

ICE officials said that Homan has responded to issues in both offices and that the latest employee survey shows that morale increased 10 percent this year. They said discrimination complaints in San Diego have declined.

The union is also highlighting allegations of officer misconduct. In one case, in December 2014, federal immigration agents in San Diego accidentally left an immigrant locked inside a van for more than 30 hours. The union did not name the man when it described the incident on its website, but The Washington Post obtained documents identifying him as Gregorio Villasenor, a Mexican national who is now 66.

ICE agents released Villasenor without taking him to a hospital or filing immigration court charges against him, which the union says amounts to a coverup because it ended his case.

Villasenor said in an interview that he declined to go to a hospital. He also said some agents told him before they released him that he could sue the agency and possibly obtain his legal papers. He said he consulted with a lawyer but was unable to find a way to obtain legal residency.

ICE spokeswoman Liz Johnson said the agency had medical personnel examine Villasenor before releasing him and investigated the incident. Officials said that the missing court case was an "oversight," and that they plan to file charges against Villasenor.

Johnson said ICE now requires agents in San Diego to fill out a checklist after each transport and have supervisors inspect vehicles at the end of each shift.

In another San Diego case from 2014, union officials criticized local managers for promoting deportation officer Thomas Malandris after he struck and injured a pedestrian in a crosswalk with his government car and told his supervisors it was the pedestrian's fault. Malandris had previously been suspended for misusing a government credit card.

Johnson said that the Privacy Act bars them from commenting on personnel matters, but that promotions are merit-based and decided by local managers.

Malandris declined a request for comment.

Watchdogs not connected to the union have raised broader issues with ICE management. A Homeland Security Inspector General's report based on inspections last year found that deportation officers had "overwhelming" caseloads and inadequate training.

Homan ran deportation operations from 2013 until Trump named him ICE acting director in January. (His title was recently changed to deputy director so that Trump could nominate him to the director's post, which is not allowed for acting directors under federal law.)

Johnson said Homan is addressing the inspector general's findings, but pointed out that the issues occurred during the Obama administration.

Under President Barack Obama, officers were told to focus on serious criminals and other high-priority cases. In January, Trump lifted those restrictions. Since then, arrests and deportations from the nation's interior have soared.