Sinn Fein President Mary Lou McDonald has said she was "profoundly shocked" when she found out about a former councillor's involvement in gangland crime.
Jonathon Dowdall was elected to Dublin City Council as a Sinn Fein councillor in 2014. He left the party and the Council soon after.
Last month, Mr Dowdall was sentenced to four years in prison for facilitating the murder of David Byrne in the Regency Hotel in 2016. He has since turned state witness in the Regency murder trial.