Characterising a crowd surge as a “stampede” or “panic” is misleading he says in that it implies the audience is in some way to blame.

“People don’t die because they’re panicking,” he says. “They panic because they’re dying…When you use the word “panic” or “stampede” you immediately look at the crowd as being at fault rather than the causality: ‘how did we let the crowd into this situation in the first place?’”

“When you try to save your own life or the lives of people around you, that’s not panic. That’s self preservation,” concert safety expert Paul Wertheimer agreed in an interview with CNN. “When you’re being crushed by 5,000 people behind you and you’re up against people in front of you who are being crushed, you’re trying to save your life because you’ve been put into a position and an environment which is beyond your control.”

Crowd surges don’t “just happen” he said. They build up gradually. “When authorities say a surge happened quickly, that’s not really how it works. It takes time to build up density in a crowd. It will create the surge or the crowd crush or the crowd collapse, which occurred over time. Crowd safety experts know this.”

The only way to prevent further tragedies is to hold concert organisers and promoters criminally liable for deaths, says Wertheimer. “Start criminally charging these promoters and agencies that sign off on these reckless events. Do that, and safety will change overnight. If nobody’s criminally charged, families of the deceased will sue; those injured will sue. And four years from now, they’ll settle with everybody. We’ll do the legal dance, and then in between and after, it will be business as usual.”