They were owned by the construction company, so since it was private property it should be up to the owners of the vandalized property to seek damages, not the police IMHO.
It doesn’t look like private property to me. Looks like the side of a public road under construction.
So, to be the devil’s advocate here...you have a narrowed lane due to construction, at night, people whizzing by at 40-70 mph, turning their head to gawk at this.
This is a safety issue. I can easily see the police getting involved without the company.
What if the person had the thing holding a big sign saying ‘OBAMA’S STIMULATION MONEY ROCKS!’ Would that have been okay?