The inventor of the Breathalyzer Machine 900 A, to determine the amount of alcohol in your blood , Dr. Greenberg used to sell the license to manufacture his machine for thousands ! Every Police Dept in the USA had to buy one or two !
He eventually became an expert witness for the Defense for $ 1,500 a trial about how his machine was deficient !
He would have "Dr Days" at local Police Dept, where he would make + $ 10,000 a day testifying his machine didn't work !
A fellow called Robert Borkenstein is generally listed as the inventor of the breathalyzer, BUT there has been quite a cottage industry that has grown around this industry. My memory is that Dr. Greenberg claimed himself around development of the 900 A machine !
In the NJSP you had to be certified to run tests, the tests and calibration of the machine had to be checked at the time of the test by you and yearly by specially trained Troopers of the Breathalyzer Unit. That was their ONLY job, travel to NJ Police Departments to reset the machines annually.
There were specific methods of observing possible drunks, special ways to insure you received a "good" breath from those under arrest, and how to insure records and memory for future testimony in Municipal (or higher) Court. Operators of MV's with BAC readings that received DWI Summonses HAD to appear in Court, represented by an Attorney that typically charged between $1,000 - $ 1,500 a case.
In NJ it costs around $ 10,000 to be convicted of DWI and get your DL back after your Suspension !
So the ONLY safe way to be safe is NEVER drink and drive !