The result will be that more guilty perps will end up in jail longer, and a couple of guys who might be lucky ('cause the lab messed up something) will get to go back on the street and try it again real soon.
I seriously doubt it will reduce the number of innocent people sent to jail.
Well, I assume the attorneys for the guilty guys will figure that out and react accordingly, but it’s at least a new tool that can be used by people to show the lab-state-prosecution relationship instead of being forced to treat lab results paid from the same purse as the prosecution as holy writ.