Welcome to the thread mrscg... . Thanx for your insight..
We've sleuthed quite a few cases in NOLO, Baton Rouge, Lafayette, etc. over the years... [abridged, in response, for focus]
Sorry, I digress.. Road debris statistics are monitored by the National Highway Administration. These stats are updated every five years, but from what I understand the reporting from many municipalities in the past has been lacking at best. Road debris consists of many objects and substances. For instance objects falling from unsecured loads of vehicles. If these items were the culprits in the rash of window shatterings it would seem that they would be witnessed or easily located, imo..
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