Model Shirley Beiger shot and killed her love for cheating. The entire courtroom cheered when she walked free.

In 1954, glamour model Shirley Beiger drove to the ritzy Chequers nightclub in Kings Cross. 

Her husband had told her he was at the dentist that night. He wasn't. Arthur Barry Griffith was at Chequers, but he wasn't alone. The 23-year-old local gangster was with three other women. 

Armed with a .22 Browning repeater rifle, 22-year-old Beiger confronted her boyfriend outside the club, before the gun went off. Griffith was shot in the face and killed.

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Less than three months later, the former Miss Australia contestant faced court, accused of killing him in a fit of jealous rage, an accusation she denied. 

According to a 1954 Sydney Morning Herald article, written at the time of the trial, the Crown told the court Beiger – whom he described as a "scorned woman" – followed Griffith to the club on August 9. She was "insane with jealousy", he said, and ultimately murdered the man who betrayed her. 

But according to Beiger, Griffith's death was nothing more than a terrible accident. 

The loaded rifle, she told the court, was across her knees as she sat in her mother's car outside the club. When Griffith pushed her, the gun went off. 

News reports at the time suggested Beiger was grief-stricken and almost inaudible as she gave evidence during the trial, telling the jury she never intended to injure her boyfriend. 

She said she "loved him until the finish". Beiger admitted feeling hurt by Griffith's dalliances, but never bitter. 

"I don't even remember the gun going off," she told the court, tears rolling down her face. 

The all-male jury believed her story, returning a verdict of not guilty for the murder charge, as well as the lesser charge of manslaughter. 

When the verdict was read, people in the courtroom erupted in cheers and clapping. Within seconds, a woman ran outside the court to share the news with the 200-odd crowd waiting outside, shouting "she's not guilty!". They, too, began to cheer, with one woman yelling, "Good on you Shirl!". 

Beiger's story will now be the subject of a new play as part of the Sydney Festival. 

The performance will take place at the same location where the trial occurred – Darlinghurst Law Courts — with audience members watching from where court-watchers observed the trial back in 1954. 

Interest in A Model Murder, staring Sofia Nolan, has been so strong, the Sydney Festival announced an extension of its three-week season.

In the dramatic live performance, Beiger gives her account of how the gun accidentally discharged during a struggle with Griffith.

Before the trial, Beiger was held at Long Bay Gaol, where she gave a lengthy interview for the publication, Truth. This account formed a basis for the script, which was further fleshed out by Guardian journalist Melanie Tait and Director/writer Sheridan Harbridge.

A Model Murder runs from January 4 to 25 at the Darlinghurst Law Courts.

Feature image: Dictionary of Sydney.