In short, the Silvester Stallone version of Judge Dredd had the real gritty look of the city and of the uniforms. the modern movie of Dredd really captured his no-nonsense, if not outright fascist, attitude and the look of the massive apartment blocks.
That's just marker on top of the watercolor paint. One of the nice abilities of marker. I put down the marker as a base, then I rendered the wall texture with the paint and then went back over it with marker.
I really appreciate you taking the time to explain that. It's a great looking effect. I've been trying different types of white paint to get a similar look so your explanation really helps. Thanks again!