[zerocrates]

Chevron says (said) that the courts should defer to agencies as the experts in their specific arenas when interpreting vague laws. This situation comes up a lot. It's quite common for Congress to delegate to an agency with only quite broad language, relying on the agency to fill in the specifics through regulation.

Practically, the major effect here is to reduce the power of the executive (and of Congress to delegate to the executive) and increase the power of the courts.

Like many of the Supreme Court's actions, it needs to be understood in the context of the years of history of Congress being in an almost total state of paralysis, so decisions that nominally "kick things back" to Congress are of enormous significance.

The decision tries to say that this doesn't affect the solidness of the many many prior cases that relied on Chevron deference, but expect a flood of challenges to regulations in basically every field.