The Dueling Machine by Ben Bova

In a near-future society, an inventor creates a device that lets two people resolve disputes by entering an exquisitely realistic simulated duel whose consequences can carry over into the real world; the machine promises a final, efficient way to settle grievances but quickly sparks legal, ethical and political battles as individuals and institutions jockey to use, control or outlaw it, forcing characters to confront questions of justice, responsibility, and the dangerous gap between virtual action and real-life harm.

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