How serving documents ensure that a party got the right ones?

Legal documents are usually served in envelopes (I am French, and this is what I get from movies or celebrity dramas).

It seems that the act of handing over the envelope (at least in the "in-person" version) is enough to ensure that the documents are known to the recipient.

The envelope could be empty, or have irrelevant documents - how is it ensured by the court that what was inside the envelope is indeed what is claimed to have been served?

In other words, how does non-repudiation work in that case?

EDIT: please note that I am asking about the non-repudiation regarding the content of the envelope, not the fact that the recipient received the envelope, or whatever the packaging for the documents is.

canadaunited-states

Service is evidenced to the court through an "affidavit of service," in which the person who served the document on the party affirms under oath how they in fact delivered the document to the party.

See e.g. an affidavit of service of a brief before the Supreme Court of the United States.

england-and-wales

Sending a document merely creates a rebuttable presumption of receipt by the recipient. This means that the starting point is that the court will assume receipt if there is evidence of service. The burden of proof then shifts to the recipient to prove that they did not receive it.

In the case of service by post this principle is codified in legislation under Section 7 of the Interpretation Act 1978:

Where an Act authorises or requires any document to be served by post (whether the expression “serve” or the expression “give” or “send” or any other expression is used) then, unless the contrary intention appears, the service is deemed to be effected by properly addressing, pre-paying and posting a letter containing the document and, unless the contrary is proved, to have been effected at the time at which the letter would be delivered in the ordinary course of post.

I recently encountered this issue at a hearing. The claimant claimed they had served a document and could provide evidence (e.g. postage receipts, witness statement, copies of correspondence). The defendant claimed they did not receive it and also provided evidence in the form of a witness statement. The court decided that on the balance of probabilities the defendant had failed to prove non-receipt and that the claimant's evidence was stronger. If it had been the other way around the defendant would have succeeded and there would have been no valid service.

Generally it will be much more difficult for the recipient to prove non-receipt than for the sender to prove that they sent it. A good counter example might be the one from PMF's comment: "I once got served the wrong documents from an attorney (they where for somebody else's case)". Here, a witness statement together with a copy of the wrong document might tip the balance in favour of the receiving party since there's unlikely to be a better explanation for why they were sent that wrong document.

californiausa

In California (and probably elsewhere in the US), the server must provide a written affidavit (CA POS-040) under the penalty of perjury. The server must be unaffiliated with the case (to be an independent uninterested party), and there are usually people who do this for a living.

Once attorneys are retained, service is usually done electronically directly between the attorneys, and then a different statement is provided to the court.

If a wrong document is served in-person (or the server lied) the recipient would need to be able to prove it. Given that it needs to contradict a sworn statement of the server, that would require some effort and evidence. If proven successfully, then the server is at risk of being prosecuted for perjury (a felony).

But people still screw it up

If you are going to court, the person who served the documents will submit an affidavit of service where they set out who, how, when, and what was served. Like any fact before the court, the other party can contest it. If they do, then evidence on the matter is advanced, including testimony, and, because service is a matter of law, the judge decides what was served.

Speaking as an adjudicator, I have had several matters where service of the adjudication application on the respondent has been an issue. Since such service is necessary to engage my jurisdiction, if it didn’t happen, I can’t make a decision which means, in practice, the claimant gets nothing.

Of course, an adjudication is not a trial or an arbitration so these matters were decided on the papers without the ability to hear testimony and cross-examine witnesses, but the illustrate the errors that can be made.