The chairman of the West Yorkshire Police Federation, Jon Christopher, told Calendar:
"Clearly Sir Norman is no longer a serving officer. It is now open to the public debate to see what, if anything, can be done against him if that's the will of the public."
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Steve Bruce expects several of his players will want to leave Hull following their relegation to the Sky Bet Championship.
Sixteen people have been arrested in connection with an illegal rave in Lincolnshire in which three police officers were injured.
A goalless draw at home to Manchester United condemned Hull to the Championship next season.