Here's your design with finishing effects, and some closeups for detail. We added a gold trim around the outer blue ring; it fits better with the horizontal stripe, and the dropshadows of the main letters keep them easily readable. The horizontal stripe now cuts off at the knotwork. The outer letters, banner type, fluer, knotwork, and gold plaque at the bottom have all been finished in a smooth, shiny gold. The blue elements have a subtle grainy texture. The tartan is a big pattern, but a big weave would look awkward. We've scaled the weave texture to find the best compromise. The "Louisville Police" letters in the shield have a 3D look and slight texture on the white. The type on the plaque at the bottom has been stamped into the metal. There are subtle textures and silver borders for the shield banner. Additional effects have been added where appropriate.
The earlier mockup is at the bottom of the page.