Email and WhatsApp in commercial deals in Mexico: how to preserve the evidence

Imagine that the price was negotiated by email, the delivery was changed on WhatsApp and the supporting record stayed on someone else's phone. If a difference with the customer or the supplier appears tomorrow, each department will hold only part of the transaction.

Before a dispute exists, decide how the business's communications will be kept. Aim for a file that makes it possible to link the proposal to its acceptance and to what was later done to perform it.

What the Commercial Code says about data messages

Article 89 of the Mexican Commercial Code (Código de Comercio) defines a data message (mensaje de datos) as “the information generated, sent, received or archived by electronic means, optical means or any other technology” [1]. The definition speaks of electronic means in general and does not mention specific applications. On that basis, in this article we treat emails and WhatsApp messages as data messages.

Article 89 bis says that legal effects, validity or binding force shall not be denied to any kind of information solely because it is contained in a data message. It adds that those messages may be used as evidence in any proceeding before a legally recognized authority and that they will have the same legal effects as printed documentation, provided they conform to the provisions of the Code itself and to the corresponding regulatory guidelines [1].

That article speaks of the medium in which the information is held. It does not say what was agreed in your transaction or who had authority to agree it. If a conversation includes an offer, a modification or an acceptance, ask for it to be read together with the rest of the relationship. If the sentence is brief, accompany it with the earlier messages and the documents it responds to.

Keep the conversation with its documents

Link the messages to the quotation, the order, the attachments and the transaction's supporting records. If an email mentions a “final version”, identify the specific file. Also keep the later changes that help explain which terms remained in force.

Keep the phone or the account where the conversation is held, complete and without deleting or editing messages. Make a backup through the company's authorized channels and note who holds each number or account. Do not leave as your only backup a selection of cropped screenshots, without dates, participants or context. Use screenshots to locate an exchange and keep separately the conversation they came from. Our article on eviction for nonpayment of rent makes a similar point about arriving with a complete evidentiary file.

Article 1298-A, located in the book of the Code devoted to commercial lawsuits, recognizes data messages as evidence. To assess their evidentiary weight, it orders that the reliability of the method by which they were generated, archived, communicated or preserved be considered first and foremost [1]. Keep that criterion in mind when deciding how you store each conversation.

The same Code lists among admissible evidence the statements of experts, public or private documents, photographs and data messages (article 1205). Expert evidence is admitted only when special knowledge of the science, art, technique, trade or industry in question is required (article 1252) [1]. Ask your lawyer whether your matter needs an expert and what material would have to be given to that expert.

Identify the people who took part

Note what relationship each participant had with the transaction and which account or number they used. Keep the documentation that can help link that person to the decisions under discussion.

For example, if purchasing asked for a modification and another person confirmed it, identify both interventions. Also gather the document that was given to the warehouse. With that sequence at hand, prepare your questions about authorization and performance.

Avoid filling gaps with assumptions. That a number is saved under a company's name on your phone is a fact about your contact list. Gather other elements that identify the participant and support that relationship.

Define who keeps the business's information

Provide for what will happen if someone changes devices, leaves the company or loses access to an account. Assign a person responsible for the commercial file and an authorized location for the files. Define who may consult them and how their delivery to the adviser will be documented.

Article 49 obliges merchants to keep, for a minimum period of ten years, the originals of the letters, telegrams, data messages or any other documents recording contracts, agreements or commitments that give rise to rights and obligations. To keep or present originals of data messages, its second paragraph requires that the information has been maintained complete and unaltered from the moment it was first generated in its final form and that it be accessible for later consultation [1]. Ask your lawyer which of your business's documents fall under that obligation.

If a claim or a significant difference already exists, seek advice before deleting information. Also identify the deletion routines and device changes you have scheduled, and do not carry them out without confirming that the conversation has been preserved.

Ask what technical preservation the case needs

The same article 49 provides for the Ministry of Economy (Secretaría de Economía) to issue the Mexican Official Standard (Norma Oficial Mexicana) with the requirements for preserving data messages [1]. NOM-151-SCFI-2016 states that purpose: it establishes the requirements that must be observed for the preservation of data messages and the digitization of documents, under articles 33, 38 and 49 of the Commercial Code. Its Appendix A describes how a data message preservation certificate (constancia de conservación de mensajes de datos) is requested and obtained from a certification service provider [2].

Ask your lawyer whether your operation needs those certificates and from when. Appendix A says that, if verification of the certificate is successful, the data message has existed at least since the date recorded in the digital time stamp and is intact [2]. Also ask what other facts would have to be proven in your matter and by what means.

Avoid altering the original files so that they “look clearer”. If you need a timeline or a transcript to make reading easier, prepare it as a separate document and identify where each piece of information came from. Keep the material that will allow it to be checked.

Arrive at the consultation with an understandable sequence

Prepare a statement of facts with known dates and a reference to each document. Indicate what was ordered, what was accepted and where the difference arose. Distinguish what you can show from what still needs to be confirmed.

Consult a lawyer when the other party denies what was agreed, when you receive or are about to send a formal claim, or before changing phones or closing an account while a difference is open. Bring the statement of facts, the documents and the details of the devices and accounts where the original conversations are held.

At QP Abogados we draft and negotiate commercial agreements and supplier contracts. If your company's deals are being closed by email and WhatsApp, we can help you document them in a contract.

Legal source

[1] Mexican Commercial Code (Código de Comercio), articles 49, 89, 89 bis, 1205, 1252 and 1298-A, Chamber of Deputies.

[2] Official Gazette of the Federation (Diario Oficial de la Federación), NOM-151-SCFI-2016, published on 30 March 2017.

The passage quoted from the Code is our own unofficial English translation; the official text is the Spanish original linked above.

This content is informational and does not constitute legal advice. Strategy and requirements depend on the facts, documents, jurisdiction and rules applicable to each case.