House Oversight and Government Reform Committee Chariman Henry Waxman (D-Calif.) says his committee will consider voting on whether or not to hold Environmental Protection Agency (EPA) Administrator Stephen Johnson and White House official Susan Dudley in contempt for failing to turn over subpoenaed documents relating to the EPA's 2007 California emissions decision.

Last month Waxman released e-mails and testimony that, he said, proved White House involvement in the decision. Waxman subpoenaed the EPA in April, demanding documents related to the decision.

In 2007 the EPA denied California's 2005 request to enforce stricter regulations on greenhouse gas emissions from vehicles. California sued the EPA over the decision in January.

Waxman has battled with the EPA over documents repeatedly since fall, publicly blasting the agency as it has missed deadlines set by the chairman for their release.