70s novella, mind control helmets, people possessed and joyridden

I'm looking for a short science fiction book, from a long time ago (most likely the 70s). It featured a world in which people could find their bodies taken over without warning and forced to do things for a period of time. The legal system had been modified around this fact.

At the beginning of the story, the protagonist had murdered someone and was arguing that he had been taken over when he did so. The court didn't believe him because the murder had taken place in what was considered a zone safe from possession.

The protagonist escaped and journeyed around, and I remember that at one point he found a cult whose members thought they'd found the secret to protecting themselves. Eventually he discovered a society of people with helmets which allowed them to possess other people. They were taking the people for joyrides, essentially: invading their bodies, going on violent or self-destructive rampages, and then hopping out again with no ill effects.

The protagonist went on at least one of these joyrides, and later was invited to join the society; instead he destroyed it from the inside. In the end, he was the only person with a helmet remaining on the planet.

I remember being enthralled with it when I first read it, and I'd love to find it again. Thanks for any help you guys can give me!

I remember reading it, but not many more details: the cult, I think inflicted pain on themselves, which made them unpleasant to possess

I think you're right. You've sparked a vague memory of them hobbling themselves or something, maybe wrapping wires around their skin so it was always cutting in?

A Plague of Pythons By Frederik Pohl. This book has been sought before, interestingly.

That's it! I was googling variations on "snake" and "serpent" to no avail, so I thought I might have misremembered the snake connection, but apparently I just had the wrong word. Thanks!

You're welcome.

You might also like The Wine of the Dreamers by John D. MacDonald, which has a somewhat similar possession problem, although the viewpoints of members of both cultures (possessors and possessed) appear in the story, and the resolution is a bit different.

The Brains of Earth by Jack Vance features invisible creatures that fasten on the brains of thinking beings and manipulate their emotions to the creatures' own benefit. Sinister Barrier by Eric Frank Russell does also. Not possession in the sense of the Pohl; the victims think their emotions and actions are their own.

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