When the delegation of congressional Democrats arrived in Texas on Monday to tour border facilities holding migrants, they were told in briefing packets and by Customs and Border Protection personnel that photos and videos were prohibited — to protect the privacy and safety of those inside.

The lawmakers followed those guidelines while they toured an El Paso facility for migrant children, operated by the Department of Health and Human Services, according to Rep. Pete Aguilar (D-Calif).

“We understand protecting kids,” Aguilar said.

But the same understanding did not apply to the two Border Patrol stations in El Paso and Clint, where the lawmakers’ phones were confiscated by CBP, and where Rep. Joaquin Castro (D-Tex.), chairman of the Congressional Hispanic Caucus, managed to capture photos and videos on a recording device anyway.

“Our border patrol system is broken. And part of the reason it stays broken is because it’s kept secret,” Castro said on Twitter. “The American people must see what is being carried out in their name.”

He went on to post photos of a dozen migrant women, who sat atop blue sleeping bags on the ground in a small concrete room. In one photo, Ocasio-Cortez is hugging a woman who was separated from her daughters and did not know where they were, the congresswoman said.

In a video Castro posted of the same women that resembles body-camera footage, Ocasio-Cortez can be heard speaking to the women in Spanish and then asking someone off camera in English about their medication and health care.

Though many members in the delegation, including Ocasio-Cortez, used their social media platforms to describe with words what they were seeing and hearing, Castro’s stealthily captured photos and videos served as a rare window into the Border Patrol stations and detention facilities that the Trump administration has made increasingly difficult to access.

“Customs and Border Protection is the nation’s largest law enforcement agency, and it’s the least accountable and least transparent,” said Shaw Drake, a policy counsel at the American Civil Liberties Union Border Rights Center. “What the members of Congress were able to do is a vitally important part of their responsibility of oversight over these agencies.”

Reporters and photojournalists are seldom granted access to the facilities, and the scant photos and video that have been published are often views from above — showing migrants gathering beneath tents and covered by foil blankets.

But attorneys, medical professionals and especially U.S. elected officials should be allowed to show up at these facilities unannounced and inspect conditions on the ground, Drake said. Even agencies such as the Federal Bureau of Prisons and Immigration and Customs Enforcement are less opaque than CBP, he said.

“It is absolutely absurd that members of Congress cannot conduct ongoing unannounced visits to facilities in their district,” Drake said. “Members of Congress have every right to inspect these facilities, and that is their duty as a coequal branch of government.”

Castro’s visual evidence of the plight inside these facilities also raised questions about why elected government officials are not allowed to have phones inside the border facilities, but Border Patrol agents are — a disconnect that led to tense moments between CBP staff and some in the congressional delegation.

A CBP spokeswoman said it is agency policy to prohibit recording devices in processing and holding areas in “furtherance of operational security as well as the privacy of individuals in CBP custody.”

At their first stop of the day, the El Paso Border Patrol station, members of the delegation were told to leave their phones in a conference room or with congressional staff while on the tour because people on past congressional visits had allegedly taken unauthorized photos.

It was a demand that the lawmakers and advocates found offensive.

“Saying you can’t record, tweet or say anything when, in fact, there is something in there the American public needs to know, it’s ridiculous to me,” said Erika Andiola, chief advocacy officer at the Refugee and Immigrant Center for Education and Legal Services.

Rep. Veronica Escobar (D-Tex.) challenged the orders to leave her phone behind and later confirmed on Twitter that she raised her voice at El Paso Border Patrol Chief Aaron Hull.

Once the delegation was inside, Rep. Alexandria Ocasio-Cortez (D-N.Y.) noticed a Border Patrol agent trying to take a “stealth selfie” with her “in a mocking manner, despite the gravity of the situation,” said the congresswoman’s communications director, Corbin Trent.

When Ocasio-Cortez “spoke sternly” to the agent about taking photos when the lawmakers weren’t even allowed to carry their phones, other CBP officials in the room laughed, Trent said. The congresswoman then demanded that the lawmakers be let into the room full of migrant women that Castro filmed.

A Washington Examiner report, quoting two unnamed witnesses, claimed Ocasio-Cortez addressed the officers in a “threatening way.” Trent said their report was an “inaccurate depiction of events.”

Ocasio-Cortez also tweeted about the interaction.

“To these CBP officers saying they felt ‘threatened by me,’ ” Ocasio-Cortez wrote. “. . . They confiscated my phone, and they were all armed. I’m 5’4”. They’re just upset I exposed their inhumane behavior.”

Earlier that day, ProPublica had published a report exposing a private Facebook group for U.S. Border Patrol agents called “I’m 10-15,” after the law enforcement code for “aliens in custody.” The group hosted xenophobic and sexist comments, remarks about the death of migrants, and sexually explicit images edited to include Ocasio-Cortez.

While touring the facilities, Ocasio-Cortez linked the behavior in the Facebook group to what she said she witnessed at the border. The congresswoman described conversations with the women from the video, who told her that they had gone two weeks without showers, had been told to drink toilet water when their cell sink broke and were fearful of retribution for even speaking to the congressional delegation.

During a news conference later, Ocasio-Cortez told reporters she was “not safe from the officers in the facility.”

“Imagine all your hateful trolls online, but with guns,” the congresswoman’s chief of staff, Saikat Chakrabarti, wrote on Twitter. “Imagine walking into a fenced area full of them. No exit. You don’t get to take any cameras or phones with you. And those trolls with guns? They’re the ones in charge of protecting you. That’s what AOC faced today.”

Other members of Congress also said they did not feel safe in the facilities.

Rep. Norma J. Torres (D-Calif.), who joined the Democratic delegation for the Texas trip, said Tuesday on CNN that she “certainly did not feel safe” while touring the detention center. “When we walked inside the facility, there were CBP agents taking selfies with us in the background,” Torres said. “None of us had a cellphone to be able to record these actions by these agents. But imagine: This is what they are doing to members of Congress in front of their leadership, so you could imagine what happens behind closed doors.”

Brian Hastings, chief of operations for Border Patrol, told CNN that they take the Facebook posts “seriously” and said that they “do not represent the thoughts of the men and women of the U.S. Border Patrol. . . . Don’t let the actions of a few be representative of the whole, is what I’d ask.”

Hastings also said “appropriate disciplinary actions will be taken” against any Border Patrol agents employed by the U.S. government. The information from the ProPublica report has been turned over to the Office of Inspector General and to CBP’s own office of internal affairs.

In a letter to Democrats on Tuesday, House Speaker Nancy Pelosi (D-Calif.) condemned the Border Patrol Facebook group and the treatment of migrants that Castro, Ocasio-Cortez and others detailed.

“We have witnessed disrespect for the House and for the oversight duty of Members of Congress to visit sites unannounced to uncover the truth for the America people,” Pelosi wrote. “We have also learned of vile, crude disrespect for children, families and, indeed, Members of Congress by some in CBP, which demands total repudiation by the Border Patrol and the Trump Administration.”

The lawmakers’ visit to the facilities this week, along with recent accounts of conditions inside from lawyers and, on Tuesday, from the Department of Homeland Security’s Inspector General, have given the public an inside look at one of the most mysterious — but in-the-news — corners of the federal bureaucracy. Now, advocates are hoping it will be enough to spur widespread change and to help end the U.S. policy of detaining migrants at the border.

“What’s super important, and what happened yesterday, is the American public got a glimpse of what they look like,” said Andiola, with RAICES. “I can’t think of people unseeing what we are seeing right now.”

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