The English international was questioned earlier on Thursday regarding the assault which took place outside a night club on Christmas Eve.
"A 20-year-old man has been arrested after an assault outside a Hale nightclub, at about 12.30am on December 24, 2008," said a police spokesman.
"The man was arrested on suspicion of section 47 assault by appointment on Wednesday February 4 and was bailed until April 8 pending further inquiries."
From his side, City manager Mark Hughes was first to back Richards, adding that the accusation won’t affect the player’s participation with the team.
"We are very supportive of Micah. He went to the police station in a pre-arranged appointment. It is an on-going situation," said Hughes.
"We are aware of that and we are supportive of him. I also believe that he can take part in the weekend."