[richardburton]

De dure, not de facto. Show me a report of someone getting arrested for it. Hence my accurate description of his ridiculous scenario appealing to a slippery-slope style train of thought. Case closed.

[chairface]

It's still not a slippery slope. It's an analogy that illustrates what would be possible, de jure. Honestly, there's no slope involved at all.

[richardburton]

It is not an analogy. What is the analogue? The slope is descending from now (you cannot get arrested for singing happy birthday) to then (you can). Slippery.