Labor 'prisoners' of unions: Ferguson

Former Labor government minister and union boss Martin Ferguson believes Labor's shadow ministry and caucus are "prisoners" of the union movement.

Mr Ferguson has told ABC's Four Corners the royal commission into union corruption is more than a "political plaything" and could potentially reform the union movement and the Labor party.

He's says too many Opposition MPs are waiting for a phone call from a trade union heavyweight to tell them what to do.