Which, IMHO, violates the Fifth Amendment, as any compelled testimony shouldn't be admissible against you, but of course our jurists gave the government a pass on that.
Don't think so. It's not any compelled testimony. The Fifth only covers compelled testimony against one self, not against others. There are some limited exceptions like lawyers, doctors, spouses but the IRS is not covered under it. You can be compelled to testify against your friend(if the information doesn't incriminate yourself), the Fifth doesn't protect against that.
If the cops seize your diary in a raid using a warrant, it can be introduced at trial. It's evidence, not testimony.
The caveat here is that you can list it as misc or various. So no admissions.
https://en.wikipedia.org/wiki/Fifth_Amendment_to_the_United_...
I’m no lawyer, but doesn’t _everybody_ have to share information once met with a court order?
As a more mundane example, a court can grant a search warrant compelling you to turn over your computer so that police can look for proof of suspected criminal activity. Likewise, they can get a court order compelling the IRS to hand over your tax returns.
It can't force someone to give potentially self-incriminating testimony (not all “information” is “testimony”, and not all incrimination is self-incrimination.)
Lawyers, doctors, and therapists (also technically doctors) do not need to share and cannot be forced.
They cannot be forced to share privileged information they may have. However, this does not protect the class of information as a whole. IE if you share your medical or legal information to a third party, they can be forced to share it.
This is not quite correct.
Lawyers, doctors, and therapists (who very often technically are not doctors of any kind), spouses, and clergy have various privileges which limit the scope and circumstances in which they can be compelled, which limits what court orders should be issued and may be raised on motions to quash such orders after they are issued.