Nah, not gay however I am guessing he’s a predator child molestor. After all he is catered to the kids.
He isn’t catered for the kids, 2000 AD (the comic that gave us Dredd, and Rogue Trooper) is for adults, it’s the British version of Heavy Meta. The two most likely things are the investigation went weird leading to the kiss and Dredd’s realization, which he then puts aside because Judges don’t have relationships; or it’s his brother trying to discredit him, the footage causes him to think, but again he puts it aside, because he’s a Judge.