Authorities are questioning the reasons why no permanent checkpoints exist in southern Arizona, the nation’s only border patrol sector without them.

Rep. Jim Kolbe, an Arizona Republican, has consistently blocked bills that would erect permanent checkpoints along the 260-mile Tucson sector border with Mexico. In fact, he has approved appropriation bills that prohibit such checkpoints.

Kolbe, senior member of the House Appropriations Committee, says money would be better spent on more equipment and vehicles for border patrol to use in securing the border from mobile checkpoints. He says permanent checkpoints would be too easy for illegal crossers to avoid.

But border patrol field agents in Arizona contend that the state’s landscape creates geographical bottlenecks ideal for permanent checkpoints. They also say vehicles and other temporary checkpoints offer no protection from extreme weather temperatures and prevent the use of more sophisticated technology.

The Government Accountability Office is currently reviewing the issue.