Volkswagen code words trip up diesel investigators

What has made it so difficult to find evidence to hold individual Volkswagen employees accountable for the company's diesel-emissions cheating scandal?

According to Bloomberg, one reason is the obscure company code words that investigators are encountering as they work through data secured from more than 1,500 laptops.

The probe has been slowed by use of dozens of terms, including "acoustic software," for the illicit technology VW used to turn off pollution controls when cars were on the road, sources told Bloomberg.

About 450 internal and external investigators have focused on about 20 employees linked to the deception, say people familiar with the probe, which is being led by U.S. law firm Jones Day with assistance from Deloitte.

Proceedings also have dragged on because many interviewees were reluctant to provide insight because they were afraid of the legal consequences, said the sources.