When the Miami Herald/Tampa Bay Times published a list Sunday of more than 700 detainees held at the A lligator Alcatraz detention facility in South Florida, it confirmed what many have suspected all along: Despite political claims to the contrary, many of the migrants being detained have no U.S. criminal convictions or pending charges.

The mayor's request comes as state and federal lawmakers prepare to tour the remote facility this weekend, amid growing scrutiny over its conditions.