How would you feel if your governement makes a no mixer law and backdates it so that you have to explain your involvement as an advertisement service for them? and user of their service as you just admitted to.
If your government punishes you for something that wasn't illegal at the time, you have much bigger things to worry about. It would be a Human Rights violation:
Article 7 No punishment without law
1 No one shall be held guilty of any criminal offence on account of any act or omission which did not constitute a criminal offence under national or international law at the time when it was committed. Nor shall a heavier penalty be imposed than the one that was applicable at the time the criminal offence was committed.
2 This Article shall not prejudice the trial and punishment of any person for any act or omission which, at the time when it was committed, was criminal according to the general principles of law recognised by civilised nations.
This means that:
The right to no punishment without law is absolute. This means that it cannot be restricted in any way.
So to answer your question: if my government would do what you suggested, it would be time to bring out the pitchforks.
Unfortunately U.K. law does not apply to USA. It is a nice law though.
Unfortunately here in the USA we shit all over that idea.
1)Read on how USA altered time served rules after the fact.
2)Read how USA alter pedophile rules after the fact.
To give you an example of how fucked the USA is we could charge Boris (ex PM) for US tax evasion anytime we want.
3)Hard to believe but true. look it up
Not fud for 1),2),3)
just facts
If the government wasnt planning to backpunish people for breaking laws then why on earth is the NSA building massive datacenters and collecting unbelievable amounts of data on everyone to store forever? You really think at some point they wont have AI going through that to try and bleed people dry in order to push their agenda?
The blockchain can be good or it can be used for evil. Chipmixer wont save you from it being used for evil.