Working as a maxillofacial surgeon in Glasgow in the early 2000s, Christine Goodall treated hundreds, if not thousands, of patients with injuries to the neck, face, head and jaw.

Once, a young man came into the hospital in the middle of the night with a knife wound across his face. Goodall dreaded telling him that it would be impossible to reduce the appearance of the scar. But his reaction surprised her. “He was very offhand about it,” she says. “Some of his friends came to see him later that afternoon and I realised why it wasn’t going to be a problem for him – because they all had one. He’d just joined the club.”

The incident has stayed with her as an indication of how bad the situation in her city had become.

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In 2005, the United Nations published a report declaring Scotland the most violent country in the developed world. The same year, a study by the World Health Organization (WHO) of crime figures in 21 European countries showed that Glasgow was the ‘murder capital’ of Europe. More than 1,000 people a year required treatment for facial trauma alone. “We were really good at patching injuries up,” says Goodall. “But I started to think: what can we do to prevent them coming here in the first place?”