If VW cheated on the tests, they should be fined heavily. Those of you who are criticizing emissions controls and tests are woefully ignorant of the improvements they have brought in air quality across the US.
New cars and trucks emit a very small fraction of the pollution from older uncontrolled vehicles. Even though some people still drive old vehicles without emissions controls, the percentages go down year by year and account for a small portion of the total cars on the road.
Since the EPA started requiring emissions controls on cars and cleaner fuels, levels of air pollution have declined dramatically -- contributing to huge improvements in air quality across the US. Diesel cars and trucks were one of the last vehicle segments to require controls, and were largely exempt for many years. Anyone who has gotten stuck behind an old diesel car or truck with no controls know how stinky and smoky they are.
Everyone has to breathe, and you can't easily avoid polluted air like you can water. So, the improvements in air quality have direct benefits to public health for everyone, leading to fewer respiratory problems, lung disease and lower death rates. How anyone could oppose that is beyond me. If you long for the good old days when cars and trucks had no controls, and fuels contained lead and sulfur, I suggest that you move to China and enjoy the smog.
Clean air is valued by many people. If VW was deliberately cheating on emissions tests, a lot of customers would buy cars from other companies. I, for one, would not buy a VW now knowing what has recently come out.