The U.S. praises Calderon for rooting out corruption at the top. But critics say the arrests reveal nothing more than a timeworn government tactic of protecting one cartel and cracking down on others.
"If there is anything worse than a corrupt and ill-equipped cop, it is a corrupt and well-equipped cop," said criminal justice expert Jorge Chabat, who studies the drug trade.
"They don't necessarily try to build networks of corruption. They prefer networks of intimidation," said Monte Alejandro Rubido, who leads Mexico's multi-agency National Security System.
