Here is a quote from the FAA's, "LAW ENFORCEMENT GUIDANCE FOR SUSPECTED UNAUTHORIZED UAS OPERATIONS"
FAA_UAS-PO_LEA_Guidance.pdf
"Other investigative methods also may prove useful, such as consensual examination of the UAS, equipment trailers and the like. However, other law enforcement processes, such as arrest and detention or non-consensual searches almost always fall outside of the allowable methods to pursue administrative enforcement actions by the FAA unless they are truly a by-product of a state criminal investigation."
It is pretty clear to me.
The vast majority (not all) of FAA UAS violations are NOT considered criminal offenses. The original discussion was about local LE enforcing UAS operations. I believe the instances you cited are considered criminal offenses and involve full-scale aircraft. I'm not sure how local LE and the FAA cooperate where those offenses occur. I think that in some instances (immigration laws) local LE have been "deputized" by the FED's and are able to arrest offenders.
Astro