Interesting, because I had worked on a Homeland Security Tahoe that was diesel. Had all the typical diesel stickers under the hood, nothing aftermarket (typical factory/SAE info stickers written in english, arabic, cyrillic and french). This vehicle was typically based out of the Bay area, but had come into the shop due to horrible emergency equipment install (and wiring).
Also a BLM Fire supervisor's Suburban that had a diesel. This vehicle was assigned to the northern California/southern Oregon area and was having a Kenwood radio. Added as a supplement to it's Bendix-King for multi-agency communications.
Nothing special about either vehicle, both were government assigned assets, VIN was typical, etc. so I assumed that this was a normal option.
The Suburban was a 2012 and the Tahoe was a 2013, by the way.
I do know that Chevrolet has introduced a 2.0L turbo-diesel to it's Cruze model line for 2015. Supposedly petter mileage and performance than a Jetta.