Annulment: How do Catholic courts evaluate evidence admission? (Fruit of the poisonous tree) Example: Say I'm married and I snoop into my spouse's personal belongings and discover some kind of evidence that, if it would be admissible, would prove beyond reasonable doubt (or balance of probabilities, whatever is the church's standard) that my church marriage is void or voidable (I'll say just 'invalid' to mean 'void or voidable'), that is for a church annulment and not church divorce (so no Pauline privilege, Petrine privilege, etc, although apparently these don't count as divorces or something).
To clarify (based on answers that are now deleted): I know what annulment is. In this example, the marriage is definitely invalid. The evidence points to behaviour that points to doubt on the intention or capacity to enter into marriage, and would do so beyond reasonable doubt (or balance of probabilities). The evidence is not about subsequent behaviour and doesn't have to be a document. Finally, If relevant, let's include the assumption that the the state marriage is invalid, but please state why the assumption is  relevant.
Question 1: Would the church consider the evidence inadmissible because it violates the church's equivalent of the US fourth amendment?

Eg Fruit of the poisonous tree: So here, I'd like to know if the church is more like the US or more like India or Ireland

Question 2: In general, how would one get an ecclesiastical warrant?

Would one need to get a civil warrant as well?

Or is there no such case where one obtains an ecclesiastical warrant but not a civil warrant?

I have a feeling we have to go by civil law here unless the law is unjust such as in North Korea or something. I mean, the couple's/respondent's/petitioner's living in a certain area and so their/h expectations of privacy would depend on the state laws.

But in the case a petitioner would seek a church annulment and not a state divorce and not a state annulment (is that possible? See my other question), would the church have to consult a state attorney?

I was thinking about Antarctica or Mars as in my other question, but the point is that one's expectations of privacy depend on one's location, if not one's state laws or lack thereof. Thus, I guess, the evaluation of evidence admission is based on such expectations. So, if one was in a Russian spaceship on Mars, then your privacy may be governed by Russian laws. And if you went on vacation to some ungoverned territory say another solar system or even time travelling to another time, there would be some expectations of privacy between humans. I guess this is where natural law may come in or something.
I suppose you are refering to some document or something equivalent. 

The code of canon law, about "The Nature and Trustworthiness of Documents" in its numbers 1540 to 1543, but specially the last one, states that if a "document is otherwise defective, it is for the judge to decide what value, if any, must be afforded them.", but I have not found reference about how the documents should be obtained to be valid. 

But is my opinion, that must be obvious and your conscience must be clearly convinced, that the information you obtained is true and you had the right to know it.