A Texas Department of Public Safety official warned troopers against using third-party messaging applications to communicate with other law enforcement agencies after body camera footage showed a trooper using Signal to help coordinate the detention of an 18-year-old high school student by federal immigration authorities.
The warning followed the publication of a video showing the trooper sending information about the teenager to U.S. Immigration and Customs Enforcement through the encrypted messaging app. An ICE agent responded with one word: “Detain.”
Emails obtained by KPRC 2’s investigative team show that concerns about Signal and other messaging platforms were not new. DPS leadership had previously warned officers that communications related to investigations must be preserved and, when required, submitted as evidence.
The latest disclosure raises questions about how law enforcement agencies document communications between officers and federal immigration authorities, particularly when those exchanges help facilitate an arrest or detention.
According to the investigation, a 28-minute body camera video recorded during a May 1 traffic stop in Austin shows a trooper pulling over a teenager who was returning home after working a night shift at a fast-food restaurant.
The student was a high school senior. During the stop, the trooper used Signal on a personal phone to send a photograph of the teenager’s identification to federal immigration authorities.
The messages shown in the footage indicate that the trooper shared information identifying the teenager as 18 and as a Mexican national. An ICE agent responded by sending information about the teen, including a federal identification number, and the message “Detain.”
Federal immigration authorities subsequently arrived and took the teenager into custody.
The trooper’s communications were visible in the body camera footage, which later became central to questions about the agency’s use of messaging apps and its record-preservation procedures.
The teenager was released in time to attend his high school graduation after his attorney filed a habeas corpus petition seeking his release. U.S. Rep. Greg Casar, a Democrat representing Austin, also pushed for the teenager’s release.
A habeas corpus petition allows a person to challenge the legality of their detention before a court.
Within five days of Austin NBC affiliate KXAN publishing the footage, DPS Deputy Director of Law Enforcement Operations Lt. Col. Jason Taylor sent an email to agency chiefs warning that officers continued to use third-party messaging applications.
In the email, Taylor referenced applications such as Signal and emphasized that officers should use agency-approved platforms instead. He identified Bridge4PS as the agency’s primary messaging application.
Taylor explained that the approved platform allows officers to preserve and transfer communications into PDF documents, making it easier to maintain records that could be subject to public information requests.
Signal is known for its end-to-end encryption and features that allow messages to disappear automatically. Those features can create challenges for agencies that must retain communications in accordance with public records requirements or preserve evidence for legal proceedings.
The emails obtained by KPRC 2 also show that Taylor had raised similar concerns in March 2024. At that time, he warned that communications exchanged through Signal, WhatsApp and other third-party apps during joint investigations could be subject to evidence-preservation requirements.
Taylor said messages involving multi-agency task forces and operations may need to be included in case files provided to prosecutors, even when other participating agencies do not submit them.
The agency’s concerns, therefore, extend beyond which messaging app officers use. They also involve whether law enforcement communications are documented and retained in accordance with applicable requirements.
In September, DPS released a redacted screenshot of the Signal exchange between the trooper and ICE agents after a public records request.
The screenshot included portions of the conversation captured on body camera footage, as well as additional messages from individuals identified as ICE agents. Some messages included requests for status updates and instructions such as “stand-by” and “release.”
The release of those messages offered another view of the communications between state and federal officers. However, questions remain about whether similar exchanges are consistently preserved across the agency.
Tom Gregor, a Houston trial lawyer and board member of the Freedom of Information Foundation of Texas, told reporters that the preserved messages were an encouraging sign but did not establish whether all officers were following the required procedures.
He emphasized the importance of establishing mechanisms to ensure communications are retained, rather than relying solely on individual officers to preserve them.
Texas law and applicable public records requirements govern how government agencies maintain and disclose records. Whether a particular message must be retained or produced depends on the applicable legal requirements and circumstances.
The Texas Department of Information Resources also confirmed that a state contract allows multiple agencies to use Bridge4PS at a pre-negotiated price. DPS had not provided details about how much the agency pays for the service.
The incident comes amid broader scrutiny of cooperation between Texas law enforcement and federal immigration authorities.
Texas has expanded coordination between state agencies and federal immigration enforcement, including through programs that authorize certain trained state and local officers to perform specified immigration enforcement functions under federal agreements.
The trooper involved in the Austin stop had received limited immigration authority through the federal 287(g) program, according to reports.
The program allows participating law enforcement agencies to enter into agreements with ICE under which designated officers receive authority to perform certain immigration enforcement duties. The scope of that authority depends on the specific agreement and training.
The use of traffic stops in immigration enforcement has also drawn attention from other Texas news organizations. In March, KUT and The Texas Newsroom reported on a separate Austin traffic stop in which a DPS trooper contacted federal authorities during an encounter that led to the detention of five men.
That case involved a different incident and does not establish that the same procedures or circumstances applied to the teenager’s detention. It does, however, provide additional context for ongoing reporting about how state traffic enforcement can intersect with federal immigration operations.
