Nobody wants their pilot, engineer, or other drivers high on anything.

But the fact remains that they don't give your pilot, engineer or other drivers a breathalyzer before they take their controls.......so why is that if drug testing is for public safety?

It's about liability for insurance companies. And if it isn't, it sure appears to be that way, at least to me.
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She was standin' alone over by the juke box, like she'd something to sell.
I said "baby, what's the goin' price?" She told me to go to hell.

Bon Scott - Shot Down in Flames