Republican Senators have invited border-security officials to describe how cartels and employers exploit the mass of migrants who are allowed into the country by the nation’s catch-and-release rules.

The rules are being defended by Democrats and their business allies who expect financial gains from the huge inflow of cheap workers, consumers, and renters. Democrats expect the migrants will vote eventually Democratic and hope the near-term chaos can be used to target President Donald Trump’s support in the run-up to the 2020 election.

The witnesses are

Chief, Law Enforcement Operations Directorate at the U.S. Border Patrol Randy Howe, Executive Director for Operations at U.S. Customs and Border Protection Assistant Director for Investigative Programs, at Homeland Security Investigations, an office within the U.S. Immigration and Customs Enforcement agency in the Department of Homeland Security

“Congress has to act,” said Wisconsin Sen. Ron Johnson, chairman of the Senate’s homeland defense committee, which is hosting the hearing.

But Democrats will use the hearing to push for easier and greater migration. “Desperation drives people into the hands of human traffickers,” according to Democratic Sen. Gary Peters, a Democrat on Johnson’s panel.