It's not insider trading if the information is public.

Yes, it can be, and I believe convictions show this - if public means "someone else could have stumbled on the info, in theory" but you were specifically tipped off where to go and when in exchange for cash; which is the kind of worry here.

But as well, policy discussions that allow no privacy tend to be very circumscribed.

For tax policy, it would make sense to solve this problem in the entirely opposite way - i.e. declare that any tax policy changes cannot take effect faster than the next fiscal year; it's also fair and much more reasonable.

Let's say they decide to put a tarrif on something a lot of people hate or think problematic. Let's say for argument's sake, 2 stroke generators. But they have a lot of power (and users) so you don't think you can swing a yearly tax. But a tax on new purchases/builds might be tractable. They get to keep all the existing ones but they can't build more. That's grandfathering.

If you give the wrong people to the end of the year, they'll grandfather in as many as they can, even if they sit unused. So now you're putting off curbing the installed base and instead you've actually created a glut. Now your tax will have zero net effect for four or five years and will make things (say, smog) far worse in the short term.

It can actually end up unwinding your tax (or regulation) --

If the people rushing to buy up the supply to simply store them off-line happen to cut off people who need them for what are sensible and essential reasons, you end up with a litany of cases of the tax causing problems paraded about as it comes into effect, and it ends up repealed or undercut because of political pressure.

(Usually 1-year window extended because "we need more time to phase it in" and by the time the second window would close, it's gutted.)

It's not just that it can end up counter productive in the short term, it's that it can undercut itself as a law as well by destabilizing a market that usually has low, but important volume.

In some places, laws already work sort of like that. Except for emergency bills, they can't take effect until something like 180 days after congress has had their final session.

It makes perfect sense, to me at least, for taxation regulations to be the same. Of course, they'd probably just default to calling all rule changes emergencies...

Sort of related: I love the idea of paying taxes. Mine are prepared and filed as soon as I can do so. I have a great time paying my taxes, to the point where I bring a bottle of wine and flowers to my accountant. But, man, I really hate the complexity and how the money is spent.

Anyhow, maybe they should only make rules for the first half of the year and then none of the changes go into effect until the first day of the year? I like your idea.

UK politicians would find that far too restrictive!

nearly every Budget affects duty on things like beer and petrol, and go into effect at midnight

people know to fill up their car the night before!