I know there's Flock staff commenting on this thread (which is great, regardless of how you feel about Flock) but just for context: Flock alerts in Chicagoland municipalities are driven by LEADS and the lookups are on license plates, not people, so they can't actually filter out failure-to-appear stops.

Right, that's why I was thinking the legislature would have to get involved. An extension to available license plate data would require approval and funding.

I think law enforcement everywhere in the US would like a way to make ALPR more useful for targeting higher risk offenders and leave the revenue generation warrants to times when the subject is being arrested for a different offense. Such an extension would maximize the utility of the investment that's already been made in ALPR hardware, software, and services.