The board of the Gate Theatre has apologised "unreservedly" to people who made allegations of inappropriate behaviour and abuse of power to it against the former artistic director Michael Colgan.

The Gate has released the recommendations of an independent review conducted by workplace relations expert Gaye Cunningham.

Ms Cunningham received input from 56 individuals, including current and former employees and board members, and people in the freelance community.

The review involved face-to-face interviews, phone conversations and email/written submissions.

The board said it apologised unreservedly to those who experienced the behaviours reported to Ms Cunningham, where people felt unable to invoke existing grievance procedures and where a culture existed in the Gate that was not conducive to people speaking out freely.

The review catalogues what Ms Cunningham reports as "credible and consistent testimonies" of behaviours that indicate Mr Colgan has a "case to answer" in respect of dignity at work issues, abuse of power and inappropriate behaviours.

Many of the participants reported feeling they had "nowhere to go" and that feeling appeared to prevent them from invoking grievance procedures.

The report makes 14 recommendations designed, the board says, to ensure the Gate is a more "positive and safe place in the future" for all who work there.

The Arts Council said it notes the report and recommendations by Ms Cunningham and the stated commitment by the Gate board to full implementation of the recommendations.