In a story from today’s Daily Environment Report, Cynthia Giles, the new Assistant Administrator for Enforcement at EPA, stated that she was looking increase the number of criminal investigators at EPA, noting that

"Criminal enforcement is a very important part of our arsenal in achieving compliance and has a powerful deterrent effect. It's important to us that we're out there and that we pursue the criminal cases.

There’s no doubt that, in a simplistic way, she is correct. Generally speaking, as the plausible threat of enforcement increases, the amount of noncompliance will be expected to decrease. However, for criminal enforcement to be a truly useful enforcement tool, EPA has to communicate clearly and unambiguously what conduct constitutes a criminal violation of environmental laws and what does not. Where language is ambiguous and interpretations shift, criminal enforcement only works as the roughest kind of hammer. It may decrease noncompliance, but it will also decrease productive, compliant, economic activity, because the risk posed by uncertainty will not be worth the reward.

Anecdotal evidence is always dangerous, but from where I sit, the risk that EPA will fail to wield its bludgeon with due care is substantial.