In portraying Irish writer and artist Christy Brown, Daniel Day-Lewis won an Academy Award and international acclaim. For Robert Softley Gale, seeing a man with cerebral palsy played on screen by a non-disabled actor was a curious affair. The theatre director’s reaction was to reimagine My Left Right Foot through the eyes of a dysfunctional amateur dramatics society. “They would go for it in a big way,” he tells me. “For them it would be about making the best show they could, it wouldn’t be about being politically correct.” His story tracks the fortunes of the Kirktoon Players, whose ambitions may exceed actual talent, as they try to boost their chances in the Scottish Amateur Dramatic Association competition by becoming inclusive.

Throw in some fabulous songs, an awkward love triangle and some robust opinions, and you have the perfect vehicle to explore the concept of casting non-disabled actors as disabled characters. “All that stuff, which is quite heavy and complex, if you put it into a musical it becomes much more enjoyable and accessible.” The songs also provide license to visit places most shows wouldn’t dream of. Lending a hand with some of these is Richard Thomas, who’s previously worked on productions like Jerry Springer: The Opera. “He’s got a lot of experience in musicals, but also with writing songs that are a little but more risqué or push boundaries. It helps asks questions in a way which is engaging and interesting.”

A sell-out and award-winning success at last year’s Edinburgh Festival Fringe drew the biggest reaction from non-disabled audience members. This collaboration between National Theatre of Scotland and Birds of Paradise, an inclusive theatre company which puts disabled artists centre-stage, My Left Right Foot places most focus on the voiced opinions of its non-disabled protagonists. It offers a gentle way of examining behaviour and perceptions. “Daniel Day Lewis created the character of Christy Brown in the film, and we all thought that acceptable and enjoyable,” Softley Galesay. “But if you get a boy or a girl in the playground pretending to be disabled, that’s not acceptable. Why’s one OK and the other isn’t? Why is it not OK to black up, but is to pretend you’re disabled? I haven’t the answer, but we need to ask those questions.” We rarely see disabled actors on stage or screen, and there’s many reasons. Too often disabled people don’t get the same access to certain education, especially with drama schools. There’s plenty of prejudice remaining in the entertainment industry. The idea disabled actors will be more difficult to work with still lingers.

This continued use of non-disabled actors focuses us on performances, instead of celebrating the stories. It’s time to reframe this. “If you’ve got a non-disabled writer, a non-disabled director and a non-disabled actor telling a story about a disabled character, there’s something a bit wrong. That’s not to say you can only tell your own story, but when disabled people are not being allowed to tell these stories we need to ask why.”

It’s a tricky balance to ask these questions, without being over-bearing or becoming cynical, but My Left Right Foot seeks a way forward. It enables us all to laugh at views instead of people. There’s been a resurgence of non- disabled white men thinking they must ‘get their voice back’. “That idea that, somehow, minorities have had it too good for too long is complete bollocks. The idea that somehow your BNP or your Trump supporter feels it’s the right time to get their voice back… We need to be aware of where that leads to.” The rise of these opinions is enabling violence against minorities and increasing exclusion. This heightened tribalism ignores the simple truth that society is complex. “Our political systems are all based on us and them. I’m a disabled guy, and I relish my identity, but it doesn’t make me special from other people. We all need to be part of a group that moves things forward. “

My Left Right Foot: The Musical comes to Theatre Royal Brighton on Tues 14 May – Sat 18 May, as part of Brighton Festival