EU: Police Football Handbook
01 October 2006
Handbook (pdf)
Defines:
"A person, known or not, who can be regarded as posing a possible risk to public order or anti social behaviour, whether planned or spontaneous, at or in connection with a football event" Point 4.7 ask for information on fans' "Reactions to decisions of the referee" and 6.8 asks for information on fans: "Political way of thinking"