This is an interesting case - whilst the T-shirt was undoubtedly offensive, I'm by no means sure it warranted arrest and prosecution - let alone a fairly harsh fine.
I know Hillsborough is emotive, but surely we shouldn't be making bad law because of it?
Surely a quiet "I'd turn that inside out if I was you, matey" from PC Plod would have been enough - much as it was with me in 1977 when I was wearing the infamous Stiff Records T-shirt?