Chicago seems to use a different (expensive) system that more closely approximates lab tests, not the $2 throwaway test kids. Illinois also has a truly fucked up legal system if they can jail people for 30 days without a preliminary hearing over a crumb of a mystery substance found in their general vicinity.
And as you said, there are other issues:
(1) Why are people being coerced into giving permission to have their cars searched when their initial violation has nothing to do with drugs. Ticket them, and unless something is in plain sight, send them on their merry way.
(2) Tiny bits of residue could have come from anywhere and anyone between the time the stop happened, and the time the car was last cleaned. There’s no proof of intent, and any such law that doesn’t require intent is a bad law.
(3) As long as someone is not driving while high, who cares what drugs they have in their car? I’d have no problem with a Breathalyzer-type system for drugs in active quantities in a driver’s system. Such things exist via saliva testing.
If addicts want to hurt themselves, let ’em.
If we insist on arresting people for victimless crimes, may I suggest a compromise? Hold THEIR CARS until lab tests come back. If the tests come back negative, apologize profusely and compensate the victim for the loss of use of their car, including any rental costs, costs from loss of working time, etc, incurred.
If the lab tests are not done in a timely manner, return of the car and payment of compensation should be mandatory. No long-term civil forfeiture.
If making false accusations and arrests begins to COST the injustice system, then maybe they’ll stop their abuse of the public.