Late to the party.
Yes, it's a Sam Browne belt but that's really common over a blouse and cross strap. It is not a LEO uniform.
I think the crowd is zeroing in on it...VFW formal uniform for parades, Veteran's Day, Memorial Day, etc. They usually have Post numbers or state insignia like the CONN lapel brass. I am sure the local VFW or Army-Navy store can fill in the details.
That should be placed behind UV-resistant glass and framed. If it's wool, a fitted blouse is about $600 today. It's really awesome!