For anybody wondering about the technical offer of Tutanota:
"Why Tutanota is the most secure email service."
"Why Tutanota is the most secure email service."
Although I see their CTO is based in the US so it is certainly possible.
Their clients are open source so you should be able to build them yourself. https://github.com/tutao/tutanota/blob/master/doc/BUILDING.m...
How would that court requirement work ?
Yeah that's the technical detail no judge has any interest in solving ;) ....like upload filters..