Images of Border Patrol agents on horseback clashing with Haitian migrants in Del Rio, Texas, were still in heavy rotation on cable news when the Homeland Security secretary promised a swift investigation.

"It will be completed in days, and not weeks," Alejandro Mayorkas told lawmakers.

But people who knew the Border Patrol — and who've tried to hold its agents accountable for alleged misconduct — knew how hard that would be.

"I chuckled," said James Wong, a former deputy assistant commissioner for internal affairs at the U.S. Customs and Border Protection.

More than six weeks later, the Biden administration has yet to announce any disciplinary action. That comes as no surprise to Wong. Before he retired in 2011, it was his job to look into allegations of misconduct against Border Patrol agents.

"They treated everybody else as an outsider," Wong said in an interview. "I was often told when I would question some of their decisions that I didn't understand, because I had never worn green."

Critics of the Border Patrol say misconduct investigations move slowly, with little transparency, and rarely deliver more than a slap on the wrist.

"These investigation and discipline systems at the border agencies are really broken and need a complete overhaul," said Clara Long, an immigrants' rights advocate with the nonprofit Human Rights Watch.

The Department of Homeland Security won't say when the investigation will be finished — but does pledge to be transparent about its findings.

The last time the Border Patrol faced this much scrutiny was in the summer of 2019. Agents were caught using a private Facebook group to share posts and images that mocked dead migrants and sitting lawmakers, including sexualized images of Rep. Alexandria Ocasio-Cortez.

"It was horrendous," said Mark Morgan, the acting commissioner of CBP at the time in an interview with NPR's All Things Considered.

"Some of the images that were out there — absolutely horrendous, wrong and not consistent with the way that CBP, or specifically Border Patrol, conducts themselves — period," Morgan said.

An internal disciplinary board at CBP found that 60 agents committed misconduct, and recommended firing two dozen of them. But only two were ultimately fired, according to a recent report by the House Oversight and Reform Committee. Most of the other agents are now back at work.

"There's a lack of accountability and a lack of oversight," said Daniel Martínez, a sociologist at the University of Arizona who's studied how CBP treats migrants in its custody. "DHS seems to be operating behind this veil of secrecy. And it seems to be this cycle that keeps repeating itself," Martínez said in an interview.

The Border Patrol's critics worry that's happening again with the investigation into Del Rio.

Images of Border Patrol agents on horseback confronting Black migrants, mostly from Haiti, drew widespread condemnation — even from the top ranks of the Biden administration.

"It's outrageous. I promise you, those people will pay," President Biden said during a news briefing.

But those agents on horseback have their defenders, too.

"The agents were sent out there to do a specific job. They did exactly what they were sent out there to do," said Brandon Judd, the president of the union that represents Border Patrol agents.

Judd says the agents were swinging their horses' reins, not whips, and that no migrants were actually injured. He argues the investigation has been flawed from the start, because high-ranking officials within the administration weighed in early on.

"Those investigators have no choice but to find wrongdoing, which is why it's taking so long," Judd said in an interview.

If you talk to critics of the Border Patrol, they actually agree with Judd about one thing: The way agents in Del Rio acted toward migrants is not really unusual.

"Some of the conduct that we saw in Del Rio, while obviously atrocious to people who saw those photos, is pretty much within normal agency practice," said Clara Long with the nonprofit Human Rights Watch.

Her group released a report last month documenting more than 150 complaints of misconduct at CBP, including serious allegations of physical and sexual abuse of migrants in custody. But it's not clear if those complaints were ever investigated, because CBP won't say.

"If the Border Patrol was a police department operating somewhere in the United States, the Department of Justice would be all over it," Long said.

But former CBP commissioner Gil Kerlikowske, who led the agency during the Obama administration, argues it's a mistake to blame all Border Patrol agents for the actions in Del Rio.

"That just kind of misses the mark," Kerlikowske told NPR. "There are people that shouldn't be there. There are people that need to be disciplined. But it really isn't the culture ... of the Border Patrol that has resulted in some of these actions that have been seen so publicly."

Still, other former CBP officials say there are deeper problems at the Border Patrol. James Wong, who used to work in internal affairs at CBP, says the Border Patrol sees itself less as a law enforcement agency, and more as a "paramilitary force."

"I've had Border Patrol agents in the past tell me that they will not retreat, and they will not give up one foot of American soil," Wong said. "They view these people as the enemy. And to me, that's troubling."

The Border Patrol's critics say that's what the images from Del Rio reveal. And why they don't expect the investigation to make much of a difference — no matter how or when it ends.

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