Mr Epere, a patched Black Power leader who has served prison terms for assault and grievous bodily harm, was not available for comment yesterday.
Mrs Williams said she did not know "anything about becoming a Black Power member" and confirmed the council had not looked into what it took to become a patched member of the gang as part of their due diligence.
Mr Epere had come before the council as an individual, not a Black Power representative, and had already spent 12 months employed by the council as a supervisor for its Taskforce Green initiative, Mrs Williams said.
Taskforce Green gives long-term unemployed unpaid, supervised parks and reserves maintenance work to help them move towards a paid job.
"He made no secrets about his past and that he'd done things he wasn't proud of in the past," she said.
"He is still a member of the Black Power gang but he wants a different future for his children.