The punishment for someone who unlawfully enters an enclosure with a dangerous animal is usually delivered without the involvement of the legal system. But when a 21-year-old man recently entered the grizzly bear pit at San Francisco zoo, state prosecutors took a different approach.

The bear pit is protected by high walls, a barricade, an electrified fence and a 14-foot deep moat, but Kenneth Herron overcame those obstacles and leapt into the pit one afternoon in September. One of two very large bears approached him and gave him a sniff; Herron narrowly escaped being mauled to death. Zoo staff averted disaster by firing a warning shot and the bears retreated. Herron was then snatched from the pit.

It might be evident to some people, even those outside professional psychiatry, that Herron is a man with mental health issues. State prosecutors, however, took the view that it would be sensible to have him punished. As he is not afraid of jumping into bear pits, precisely what sort of deterrent sentence the prosecutors wanted Herron to get is not clear.

Herron was prosecuted for criminal trespass and “disturbing dangerous animals in a park”. But the charge of criminal trespass was thrown out by Judge Wallace Douglass. The offence, under the Californian Penal Code, was designed to catch squatters and involves entering “and occupying” someone else’s property without their consent. According to People v Wilkinson (1967), “occupying” means staying for some time and, as Herron didn’t do that, the trespass prosecution was ruled to be inappropriate.

On the charge of disturbing wild animals in a park, the jury had to agonise over whether the bears were, in fact, disturbed. In what way could two 500-pound omnivores be disturbed by a single unarmed man? And looking at who was most disturbed in the pit on that day, the bears are not an obvious choice: Herron said he was there because he had heard the voice of Tyson Beckford, the model and actor, instructing him to rescue a damsel in distress.

After the trial, one juror said that the jury was not convinced that the bears were disturbed because they didn’t bound over to Herron as soon as he entered their grotto. Ultimately, though, the jury acquitted him as there wasn’t sufficient evidence that he knew what he was doing when he entered the enclosure.

Gary Slapper's new book Weird Cases is published in December by Wildy, Simmonds & Hill

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