The movie's name is DREDD so the costume designer, Michael O'Connor, got approval on the design of Judge Dredd's costume first, before moving on to the other Judge Costumes. This means Judge Dredd's costume is the Standard. All other Judge costumes are based around Dredd's look. The links in the navigation bar above go into detail on all the parts of a Judge's costume.
The design department went with a blocky, angular, and utilitarian design than the more 'decorative' design that you get with a lot of sci-fi films these days. They stayed away from branding Dredd with his name all over the costume. They opted for the more subtle approach.
Key principal costumer, Rob Allsopp, and Michael O'Connor always aimed to make the Dredd costume believable, but functional. The zippers had to be the right kind of metal zippers that you would find on a real motorcycle jacket. The leather used on the gloves had to be a certain weight and quality. The boots had to allow movement, but still give protection.
This attention to detail does not come cheap. Even doing a 'low-budget' Dredd replica costume, you should expect to spend about $350-$700, depending how acccurate you want to get with look and feel. If you go for a "screen accurate" replica costume, expect to pay over $2500.00 USD for all the pieces-and-parts. Leather is not cheap, nor are screen accurate props.
Here is a Printable Checklist for helping keep track of your costume build.