Re: and basically impossible to test for.
No, diesel-gate demonstrated that the US standard emissions test was not fit for purpose.
Then why was a code written to cheat the system and deployed worldwide?
Ok, how about another example? What about 737MAX MCAS?
Boeing told customers that the MCAS was safe and took the FCC for a "ride". What independent body verified this? The FCC.
The secret is out: Boeing staff "seconded" to FCC are certifying their own work.
I will repeat what I said previously: Independent bodies (plural) need to verify what the manufacturer claims.