Maybe as there's more evidence it's harder to convict innocent people to pad the metrics? I have no idea, but there's a lot of possible causes for correlations like this.

I was surprised to not see IR beacons on LEO units. In military operations with air surveillance, individuals/vehicles often use IR flashing and IR reflection to mark themselves to air assets. If MPD has the money for 1) an air surveillance unit (this cost is not trivial; SFPD, for example, hasn't had their own aviation section in decades due to the cost), and 2) decent thermal optics on said surveillance unit, then it surprises me they don't spring for sub-$100 IR beacons to distinguish their own personnel from everyone else, and enable rudimentary "blue force tracking", as it were.