We've all seen how this works. Users running Waze and typically driving over the limit slow down when approaching a speed trap and accelerate immediately after passing it.
Several countries, including France, have banned police reports in mobile navigation apps specifically to prevent users from warning others about the location of law enforcement. Their reasoning, besides that a police report allows speedsters to escape unpunished, is that criminals could also use the data to avoid officers on the ground specifically searching for them.
Think of someone running away from the police. If they run Waze, they could use the police reports within the app to use only routes where patrol cars haven't been flagged.
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