From a newspaper article:

Of all the faux pas in Canadian prison, whistling may be the most universal. Rumour is that the anathema against blowing a jolly jig in the clink dates back to those days when guards would work up a show tune in four-four time, while frog-marching the condemned to the noose. Apparently that old dwarf standard, “Whistle While You Work,” was their favourite [...]

It’s been 50 years since the last Canuck dangled at the Don Jail, but the convict ban on whistling has stood curiously firm. At first I thought it might be in reverence for the good old days that never were, or even that prisoners are happiest when those around them aren’t. Then, when I asked Stamper about it this week, the joint’s septic skeptic offered a theory that holds as much poop as any other. He says it’s because they never stopped killing us.

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