The dust is still settling on the revelation that millions of diesel vehicles have been circumventing emissions regulations. The scandal highlights the difficulties of enforcing effective regulation to protect a common good: the atmosphere. It also hints at future tensions that could arise between those tasked with protecting the planet and the industries that damage it.

On the face of it, Volkswagen's activity would seem to be the epitome of a 'green crime'. But things aren't so simple. There is a fine line between an offence and a crime, as Angus Nurse, Senior Lecturer in Criminology at the University of Middlesex, explains. The tension between these two concepts is likely to increase as policymakers seek ways to reduce greenhouse gas emissions across the board.

Politicians could decide to legislate against the emission of greenhouse gases beyond a certain level, thereby criminalizing corporations and industries that fail to comply. But that would be a bold move, Nurse says. Politicians don't like sending corporations to jail. They would much rather settle out of court, as they have in the past in cases such as the Deepwater Horizon oil spill, of which BP is still feeling the financial effects.

That implies continuing to regulate. But, as the diesel emissions scandal shows, there must be effective enforcement, and a large enough punishment, for such regulations to stimulate compliance.

Public pressure can aid this. It helps if a charismatic species is involved. Regulators across the world are looking at revising laws on the hunting and import of trophy animals in response to the killing of Cecil the lion by Walter Palmer.

So is Volkswagen the charismatic species of emissions regulation? There are similarities between the cases. In both, the victims and perpetrators seem relatively clear cut. And there is likely to be a similar fall-out, with tightened regulation and greater scrutiny of the respective industries. But there are also wider lessons for environmental policymakers, including those tasked with tackling climate change.

The emissions scandal shows how an environmental harm can go from being hidden to a public offence. Industries must be wondering how long it will be until regulators decide such activities are not just offensive, but criminal.