A federal appeals court has set the briefing schedule for the three cases it is handling concerning the legality of U.S. EPA's greenhouse gas regulations.

There are four rules under the legal microscope before the U.S. Circuit Court of Appeals for the District of Columbia, but two have been consolidated into one case (Greenwire, Dec. 14, 2010).

In all three cases, no arguments have been scheduled yet. The briefing, with opening briefs due in May and June, will go on until the end of this year.

The same three judges will consider the three cases, but the court has not yet revealed who they will be.

The four rules industry groups such as the U.S. Chamber of Commerce are challenging are:

• The "timing" rule that requires that new controls of greenhouse gas emissions from stationary sources would be triggered on Jan. 2, 2011, the day that new motor vehicle standards go into effect.

• The "tailoring" rule that interprets the Clean Air Act in such a way that only major polluters are required to obtain permits for greenhouse gas emissions.

• The "endangerment" rule that focuses on EPA's initial decision in which it held that greenhouse gases are harmful.

• The "tailpipe" rule that adopts new standards for car and light-truck emissions.

The timing and tailoring rules are the two that have been consolidated.

Click here to read the briefing schedule for the consolidated cases on the timing and tailoring rules.

Click here to read the briefing schedule for the endangerment finding rule.

Click here to read briefing schedule for the tailpipe rule.