The discovery of two hate-filled Facebook groups for former and active Border Patrol agents leaves US Customs and Border Protection with only one choice: It’s time to clean house. And conservatives should be leading the calls for change.

On a Facebook page with 9,500 members called “I’m 10-15” (a reference to the Border Patrol code for “aliens in custody”), members posted racist, sexist and xenophobic comments and memes. They joked about the deaths of migrants and children being carried through the Rio Grande in trash bags.

A member posted a sexually explicit, Photoshopped image of Rep. Alexandria Ocasio-Cortez with the caption: “Lucky Illegal Immigrant Glory Hole Special, Starring AOC.” One member shared the photo of the drowned bodies of Óscar Alberto Martínez Ramírez and his 23-month-old daughter, Valeria, musing whether the picture could have been faked and asking: “Have y’all ever seen floaters this clean?”

Similar posts were found on a second Facebook page called “The Real CBP Nation,” including a meme of a border agent with a man against the hood of his car and the caption: “Feelin kinda cute. Might separate some families today.”

The news site ProPublica, which first blew the lid off the secret groups, was able to connect certain participants to Facebook profiles that appeared to belong to real CBP agents. The bigoted, dehumanizing language used by these agents is even more stomach-turning in the face of increased reports of neglect and mistreatment of migrants at the border after a group of lawyers visited a facility in Clint, Texas.

Agents punished lice-infected children for losing a shared comb by forcing them to sleep on the floor without mattresses or blankets, according to The New Yorker. The New York Times reported that “children as young as 7 and 8, many of them wearing clothes caked with snot and tears, are caring for infants they’ve just met.” The lawyers claimed that children were denied showers, clean clothes, toothbrushes and soap.

The rhetoric on the Facebook pages gives credence to these accounts and ammunition to critics of the Trump administration’s handling of the border crisis. After all, it’s much easier to believe stories of hostile and vindictive agents at the border when agents on Facebook seem to be confirming that they see migrants as less than human.

If this is how they speak online about the people under their care, how do they treat them in person?

Top Department of Homeland Security officials condemned the posts and promised to open an investigation into the Facebook group. Border Patrol chief Carla Provost promised that “any employees found to have violated our standards of conduct will be held accountable.”

But according to a report by Politico, officials at CBP have known about the Facebook page for years. Indeed, concerned agents reported bad behavior by the group in 2016. A former DHS agent told Politico that CBP staffers would monitor the page to see “what people are talking about.” So if the agency knew, why didn’t it crack down years ago?

If Provost understands how serious the situation is, and how bad this looks for CBP, she won’t just hold an investigation behind closed doors and quietly get rid of a few of the worst offenders. With reports of abuse flooding in and public trust in the professionalism of Border Patrol agents disappearing altogether, the CBP needs to make it clear that bigotry and abuse won’t be tolerated.

Institutions build culture from the top down. Kicking out the bad eggs dense enough to reveal their disdain for migrants online won’t repair a broken institutional culture. If racists who could have a tendency to abuse migrants are slipping through the cracks, the entire system of how agents are vetted needs to be changed. People at the top should be held accountable.

Conservatives, who emphasize the inherent, God-given dignity of every person, should be especially outraged. As should immigration restrictionists, who shouldn’t want their cause to be conflated with racist abuse. It’s possible to be tough-minded on immigration — and humane.

Twitter: @BKERogers