Chris Hayes explains how Dick Cheney's son-in-law deregulated chemical plants

MSNBC host Chris Hayes on Thursday night explained the key role Dick Cheney's son-in-law played in keeping chemical plants free of regulations.

Concerns were raised in 2002 that chemical plants in populated areas -- like the one that recently exploded in West, Texas -- were vulnerable to terrorist attacks.

The heads of Department of Homeland Security and Environmental Protection Agency had planned to regulate the security of chemical sites, but Dick Cheney's son-in-law Philip Perry stepped in and informed them they lacked the authority to do so without congressional legislation.

At the time, Perry was serving as the general counsel of the Office of Management and Budget at the White House.

"Basically, the Bush administration from above pulled support for that bill because the chemical industry does not want to be regulated by the EPA," Hayes said.

"Fast forward to 2007, and Philip Perry -- again, Dick Cheney's son-in-law -- is at the Department of Homeland Security as general counsel. What he managed to do in an appropriations rider is slip in industry friendly language into the bill that moves the task of regulating chemical plants from the Environmental Protection Agency to the Department of Homeland Security. But DHS is given none of the tools it would need to do that."

Barack Obama introduced legislation to regulated chemical plants as a U.S. senator in 2006, but his bill was blocked by Republicans. Recently, the Obama administration has considered allowing the EPA to once again regulate the plants, but has faced a backlash from the chemical industry.

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