Meanwhile the Supreme Court has now swept aside longstanding legal precedent and its ruling

today overturning that Chevron doctrine, majorly curtailing the power of federal agencies

to interpret the laws they regulate.

The decision is expected to have far-reaching implications on everything from the

environment to health care.

For a closer look at the overturning of the Chevron precedent, we're joined now by Andrew Mergan. He spent three decades

as an attorney for the Department of Justice, Environment and Natural Resources Division.

He now heads the Emmett Environmental Law and Policy Clinic at Harvard Law School.

Thanks so much for being with us.

Thank you, Jeff.

And as on to mention, the Chevron case is obscure but has a huge impact.

It's basically shorthand for a longstanding tradition

that says if there's an ambiguous statute,

the courts defer to the agencies

in their interpretation of how to read that statute because the thinking has always been

that the agencies have the expertise. Today the Supreme Court said, nope, that's no longer the case.

How big a deal is this?

I think in a short term it's a very very big deal. I think that

we're going to see an enormous number of challenges to government regulations in

the environmental area, in food safety, in health care,

health care administration, there will be many, many challenges.

And the lower courts and the justice department that

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