The title of David Hare’s Murmuring Judges comes from an ancient expression which means “to speak ill of the judiciary” - amazingly, this is still an offence in Scottish law. The play offers a panoramic view of the British legal system, showing how idealism is corroded by cynicism. First put on in 1991 as the second in Hare’s trilogy about British institutions, it follows two female high-fliers - barrister Irina and police officer Sandra - as they try to get justice for Gerard, a young Irishman who played a minor role in a robbery, but who’s been sentenced to five years in prison.

In order to get information from the real villains, copper Barry has bent the rules. Irina and Sandra want the truth to come out, but they both get bogged down in the indifference of their colleagues. Rachel Kavanaugh, who co-directs the trilogy with Jonathan Church, says: “Murmuring Judges is the only play of the three that I didn’t see when they were first put on, so I’ve come to it fresh.” She thinks that of all the plays in the trilogy it’s the one which has the strongest and most compelling story, with the experiences of the two idealistic women counterpointing the attitudes of their more realistic, and cynical, colleagues. “The play is an epic which examines the whole legal system by looking at three areas: the bar, the prisons and the police stations. Hare did meticulous research, as if he was going to write a documentary - and then turned it into fiction.”

Kavanaugh is especially struck by the realism of the jokey scenes in the charge room of the busy police station. “The canteen-culture jokes seem to be a way of keeping up morale in the face of despair.” Hare’s intention is not to blindly attack the legal system “but to suggest ways of refreshing it”. In a way, says Kavanaugh, the women are Hare’s voice in the play. She agrees that they are both idealistic, but hopes that young audiences “will respond to the story and to what Hare is trying to say”.

The main conflict in Murmuring Judges is summed up by the “urgent question of whether it is possible to work through the system and achieve changes”, or whether those that want change are inevitably disappointed and marginalised. “Both Irina and Sandra try and change things from within.”

Although the trilogy is set 10 years ago, Kavanaugh is conscious of how little has changed since then. “I think the play remains relevant - especially the way that people working in public services have to cope with vast amounts of paperwork as well as getting on with their jobs.” This will surely ring bells with teachers.

Murmuring Judges runs from April 4-19 Box office tel: 0121 236 4455 For education workshops, teachers packs etc, tel: 0121 245 2092 www.birmingham-rep.co.uk