Sia is gearing up for the release of her debut feature film next year, but the singer has found herself on the defensive, after her decision to cast dancer Maddie Ziegler as an autistic teen was criticised.

This week saw the release of the first trailer for Music, which stars Ziegler as the title character, a non-verbal teenager who finds herself in the care of her sister, played by Kate Hudson.

After tweeting out the trailer, however, Sia was criticised for the decision to cast an “able bodied & neurotypical” actor to represent an autistic character, and for the film’s seemingly “infantilising” tone.

At first, she defended the casting process, writing:

I actually tried working with a a beautiful young girl non verbal on the spectrum and she found it unpleasant and stressful. So that’s why I cast Maddie.”

She went on to say that “a few actors on the spectrum” were considered before the decision was made to cast Ziegler, and that it would have been “cruel” to cast the film another way:

Things became more heated when another follower accused her of excluding neuro diverse actors from the film. She replied:

“I cast thirteen neuroatypical people, three trans folk, and not as fucking prostitutes or drug addicts but as doctors, nurses and singers. Fucking sad nobody’s even seen the dang movie. My heart has always been in the right place.”

Things became a little more heated, and when one performer tweeted that she and others could have appeared in the film “on short notice” if asked, Sia snapped back “maybe you’re just a bad actor.”

The National Autistic Society of the UK were critical of the casting choice, joining the conversation to say “Sia has got this one wrong … there are so many talented autistic actors out there.”

The singer has asked people to watch the film before judging it. Music and its accompanying soundtrack album are due for release in February.

Image: Getty Images / Stefanie Keenan