A border agent who patrols the Rio Grand Valley in Texas told the Senate Wednesday that illegal immigrants continue to stream into the U.S. from Mexico because they are confident they’ll be released quickly by U.S. authorities.

“Most believe that they will either not be caught, or even if they are caught, they will not be deported back to their home country,” Agent Chris Cabrera told the Senate Homeland Security & Governmental Affairs Committee in prepared testimony. “The UACs and family groups we detain are acutely aware of the fact we will not hold them until they are adjudicated.”