“If you do a film about the Holocaust, you’re guaranteed an Oscar,” goes the famous Kate Winslet joke in Extras. The same can be said for an actor doing a film about disability. Unless you’re a disabled actor, that is. Then you’re lucky to even get the part.

This week, when Eddie Redmayne won a Golden Globe for his portrayal of Stephen Hawking in The Theory of Everything, he became the latest in a long line of non-disabled actors to portray disabled characters. And to walk away – literally – with an award for doing so. From Daniel Day Lewis in My Left Foot to Dustin Hoffman in Rain Man, the ability to play “disability” is a definite asset for an actor, a source of genuine acclaim.

But is this as harmless as mainstream audiences seem to see it? While “blacking up” is rightly now greeted with outrage, “cripping up” is still greeted with awards. Is there actually much difference between the two? In both cases, actors use prosthetics or props to alter their appearance in order to look like someone from a minority group. In both cases they often manipulate their voice or body to mimic them. They take a job from an actor who genuinely has that characteristic, and, in doing so, perpetuate that group’s under-representation in the industry. They do it for the entertainment of crowds who, by and large, are part of the majority group.

Daniel Radcliffe, centre, with Sarah Greene and Pat Shortt in The Cripple Of Inishmaan at the Cort Theatre in New York. Photograph: Andrew Toth/Getty Images

The explanations for “cripping up” are obvious. The entertainment industry is a business, after all, and stars sell. When Daniel Radcliffe played a disabled orphan in The Cripple of Inishmaan this won more headlines for the production than if a disabled, lesser-known actor had been cast. On a practical level too, perhaps hiring a non-disabled actor is easier. The ability to walk allows Redmayne to portray Hawking before being diagnosed with motor neurone disease. But I can’t get away from the fact that, if these arguments were made for white actors “playing black”, our outrage would be so great that the scenes would be left on the cutting room floor.

There’s a theory of why non-disabled actors playing disabled characters leads to success: audiences find it reassuring. Christopher Shinn, a playwright who had a below-the-knee amputation, describes the act of watching a disabled character being played by an actor who we know is really fit and well as allowing society’s “fear and loathing around disability” to be “magically transcended”.

When it comes down to it, Shinn says, “pop culture is more interested in disability as a metaphor than in disability as something that happens to real people”.

Daniel Day Lewis in My Left Foot. Photograph: ITV/Rex Features

After all, disabled characters create powerful images and sentiments for audiences. They can symbolise the triumph of the human spirit over so-called “adversity”. They can represent what it is to be “different” in some way, an outsider or an underdog who ultimately becomes inspirational. These are universal feelings every audience member can identify with. And there is something a little comforting in knowing, as we watch the star jump around the red carpet, that none of it – the pain or negativity we still associate with disability – was real.

Perhaps that’s part of the problem. Perhaps as a society we see disability as a painful external extra rather than a proud, integral part of a person, and so it doesn’t seem quite as insulting to have non-disabled actors don prosthetics or get up from a wheelchair when the director yells “cut”. But for many disabled people in the audience, this is watching another person fake their identity. When it comes to race, we believe it is wrong for the story of someone from a minority to be depicted by a member of the dominant group for mass entertainment. But we don’t grant disabled people the same right to self-representation.

Perhaps it is time to think before we next applaud “cripping up”. Disabled people’s lives are more than something for non-disabled actors to play at.