In MA they supposedly have some of the strictest testing in the nation... they made garages buy these huge $80,000 automated diagnostic systems that do most of the testing for them and report it directly to the RMV. Works with the computer in the car. Cars 15 years old (last time I checked) could still be done manually and were exempt from emissions. It is suppposed to be foolproof.
The modem pool it uses is unreliable at best. Rather than fix that, they implemented a "if the modem pool doesn't work, you can do the tests manually, and send it in later another way. My car hasn't been tested with the tester in years despite being a Civic in good repair. The guy just looks at it, asks me if everything works properly, and slaps a sticker on it.