Common law and civil law disagree about who has to hand over documents

A genuine fork in the road

In some systems a party to a civil claim is required to search for and produce documents relevant to the issues, including those that damage its own position. In others a party produces what it chooses to rely on, and obtaining anything further requires a specific application identifying particular documents. That is not a detail of procedure. It shapes the entire economics and strategy of litigation.

The broad tradition-based split — extensive obligations in common law systems, narrower ones in many civil law systems — is a useful starting point and is no longer a reliable rule. Common law jurisdictions have spent years restricting the scope of disclosure because of cost, and several civil law systems have introduced targeted production mechanisms. The safest assumption is that the position must be checked wherever the dispute will actually be heard.

Preservation comes before anything else

Whatever the system, the obligation not to destroy relevant material generally begins earlier than the formal procedure does. Once litigation is reasonably in contemplation, routine deletion policies, mailbox clear-outs and device replacements become dangerous, and in many jurisdictions destroying material in those circumstances attracts serious consequences ranging from adverse inferences to sanctions against the party or its advisers.

For an organisation this means suspending automated deletion and telling the people involved to keep things. For an individual it usually means something simpler: do not delete messages, do not wipe a phone, do not tidy up a file. Material that looks unhelpful is often less damaging than the appearance of having removed it, and the second impression is very hard to undo.

Search, proportionality and electronic material

Where a search obligation exists, its scope is usually governed by reasonableness rather than by perfection. Systems ask what a proportionate search looks like given the value of the claim, the complexity of the issues and the significance of the material likely to be found, and a party is generally expected to explain what it searched and what it did not.

Electronic material has driven most of the reform in this area. Messaging applications, collaboration tools, cloud storage, backups and personal devices used for work have all expanded the universe of potentially relevant documents far beyond what the older rules contemplated. The resulting cost is one of the main reasons for the narrowing of disclosure obligations in several jurisdictions, and the technology continues to move faster than the procedure.

Privilege and other reasons for withholding

Not everything relevant has to be produced. Communications between a party and its lawyers for the purpose of legal advice are protected in most systems, though the scope of that protection differs considerably, particularly regarding in-house lawyers and communications with third parties. Material created for the purpose of pending litigation frequently attracts protection as well.

Other grounds exist too: protection against self-incrimination, confidentiality obligations that may be managed by restricting who sees the material rather than by withholding it, data protection constraints where personal information belonging to others is involved, and public interest grounds. Privilege can be lost by disclosure to the wrong person, which is why forwarding legal advice casually is a bigger risk than it looks.

Getting documents from someone who is not a party

Frequently the crucial material is held by a bank, an employer, a regulator or a platform with no involvement in the dispute. Most systems provide a route to compel production by a non-party, and it is generally narrower and more demanding than the obligation between parties: the applicant usually must identify the documents with some precision and demonstrate their relevance.

Cross-border requests are harder again. Obtaining evidence located in another country typically involves international arrangements or judicial cooperation channels, which are slow and sometimes unavailable. That is worth knowing at the beginning of a dispute rather than at the point when the evidence is needed, because it may affect where a claim should be brought at all.

Why this decides more disputes than it should

Disclosure is where many cases are actually won and lost. A document neither side expected surfaces, the picture changes, and the matter settles. It is also where much of the cost sits, and where a party with far greater resources can apply real pressure on one with fewer — a criticism made of broad disclosure regimes with considerable force.

What obligations apply, how far a search must go, what privilege protects and how non-party production works are all matters of local law that differ profoundly between systems, and they have been reformed repeatedly. Nothing here is advice about a particular dispute. The universal points are to preserve everything from the moment a dispute is foreseeable, to avoid destroying or tidying anything, and to take advice from a qualified lawyer early — because limitation periods run in the background and an internal complaint to the other side does not usually stop them.