As numerous political probes over the years have famously shown, once investigators dig into the circumstances around an alleged crime, anything can happen.
The September 2015 announcement by the EPA that VW Group engineers had admitted to deliberate cheating on U.S. emission tests of the company's "clean diesel' engines may prove to be another case in point.
Even as Volkswagen, Audi, and Porsche continue to buy back or modify more than half a million diesel cars in the U.S., investigations into the German diesel deception are expanding in Europe.
Today, we got what could prove to be a bombshell: a report that the European Union is investigating all three German makers for colluding to manipulate software and set standards for diesel emissions.
The details are said to have emerged from investigations into the actions of VW Group engineers, which German authorities have been probing since the 2015 revelations.
2015 Audi Q7 TDI
If true, the summary provided by Autocar is damning:
Acting on evidence provided by a former Volkswagen employee, the EU has opened the cartel investigation following claims that up to 200 employees from Audi, BMW, Mercedes-Benz, Porsche and Volkswagen were involved in the secret, closed-door meetings.
During these encounters, the German car makers are said to have swapped vital information on methods to circumnavigate test procedures for CO2 and particulate emissions as well as SCR (selective catalytic reduction) thermo switching, among other manipulations.
The talks are said to have begun as early as the 1990s, with one specific meeting have taken place on the sidelines of the Paris auto show in 2010.
Among the items on which the makers collaborated were the size of tanks for diesel emission fluid (urea solution), with the German makers reportedly agreeing to keep their tanks under a certain volume to aid in packing the cars.
2016 Mercedes-Benz E250 BlueTec
BMW and Daimler's brand Mercedes-Benz make up two of the five brands involved, but Audi, Porsche, and Volkswagen are all owned by VW Group.
We'll have more on this story as it unfolds; if the reports are true, however, it would indicate that the pain and cost of the diesel deception in Europe is only starting for BMW and Daimler.
VW Group has already said its cost for settlements in North America for the Volkswagen diesel emission scandal, both civil and criminal, is more than $25 billion.