[stavros]

Really? Doesn't a spouse have a right to privacy? I don't see how getting married makes you forfeit privacy rights you otherwise have.

Unless you mean that there's no legal issue with obtaining data in anyone, which is a much larger problem.

[ButlerianJihad]

There is a legal concept here of “spousal privilege” similar to that between attorney-client or priest-penitent. So a spouse with “information” could not be compelled to divulge it.

But if you mean husband and wife keeping secrets hidden from each other, that is not really a thing, except for normal human limits and boundaries, and in a marriage, the spouses should probably expect a reasonable minimum of that.