Mailboxes are established by property owners within the highway rights-of-way. A county or town could adopt an ordinance that specifies the type of placement of mailboxes to prevent them becoming a fixed hazard.
The other aspect of mailboxes to consider is the accidental damage to mailboxes in connection with the municipality's maintenance operations, particularly snow and ice removal. There is no right of the property owner to recover against the municipality for the accidental damage to mailboxes. Repairs are a judgmental decision of the superintendent.
No person shall throw or deposit upon the highway any glass bottle, glass, nails, tacks, wire, cans, snow, or any other substance likely to injure any person, animal or vehicle upon such highway.
Any person who drops, or permits to be dropped or thrown upon any highway any destructive or injurious material, or any material interfering with the safe use of the highway shall immediately remove the same or cause it to be removed.
Any person removing a wrecked or damaged vehicle from a highway shall remove any glass or other injurious substance dropped upon the highway from such vehicle.