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Not sure what it deters, but it is a deterrant.
Actually, there were pre-guillotine machines around since the middle ages. such as the Halifax gibbet
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Halifax had held the right to execute criminals since 1280. Although there is early reference to a gibbet, including a report that the first person to be beheaded by it was one John of Dalton in 1286, formal records of victims did not begin until 1541, when the town acquired a fixed machine which used a heavy axe-shaped iron blade dropping from a height of several feet to cut off the head of the condemned criminal.
And the Scottish maiden that was
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I have to admit that yet another of the Constitution's flaws is the lack of "cruel and unusual" punishments.
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I'm sure Benjamin Franklin liked giving head and should have in that manner. It would also make a really nice Mount Rushmore knock off: Jefferson, Sam Adams, Washington, Hancock and the rest of them on the Old State House Roof in Philadelphia (AKA Independence, or Treason, Hall)
That would make the point that the Second Amendment wasn't about fighting the government.
Alas, Choppping heads off and putting them on poles, hanging, drawing and quartering, and burning at the stake are tools barred by the US Constitution...and probably a few human rights treaties to boot.
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There is also this fun toy that you can buy at buy.com for a mere $8,053.45 or here for a mere $6,850.00. One seller even offer a time payment option. The description says The blade comes screeching down at high speed and a strobe light kicks in as your patrons are sprayed with blood (water). An unsettling effect that sends them running and screaming!
Yeah, I bet!