US Lawyers Walk Fine Line On Privilege, Work Product in Mexico

For multinational companies, the confidentiality of legal communications is a critical concern, especially when operations span jurisdictions with vastly different approaches to attorney-client privilege and the protection of legal work product.

While the principle is foundational in the US, its application and enforcement is murky in Latin America, exposing companies to significant legal and practical risks during cross-border investigations.

Attorney-client privilege and work product are cornerstones of the legal profession in the US, but their strength depends on where you are and who is providing the legal advice. For multinationals, understanding these differences—and planning accordingly—is essential to safeguarding sensitive communications and managing legal risk in cross-border investigations.

US Approach

In the US, attorney-client privilege protects confidential communications between clients and lawyers for the purpose of seeking or providing legal advice. The privilege belongs to the client, and only the client can waive it.

US courts enforce this right, generally excluding privileged information from evidence. Exceptions exist, such as the crime-fraud exception, but overall, the system is designed to encourage open, honest communication between clients and their attorneys.

Closely related is the work product doctrine, which shields materials prepared in anticipation of litigation—such as documents, notes, and legal strategies—from disclosure. This allows lawyers to prepare cases without exposing their tactics.

If law enforcement seizes computers or records, the company can petition the court to prevent review of privileged or work product materials and to implement safeguards ensuring agents don’t access protected communications.

Latin America

In contrast, many Latin American countries have less robust and inconsistently enforced privilege protections. Although laws in places such as Mexico, Peru, and Chile require lawyers to keep client information confidential , privilege is often treated as a lawyer’s duty, not a client’s right. This distinction can have major consequences, especially when authorities or courts decide whether to safeguard the privilege and work product during investigations.

The US concept of work product privilege is weak or largely absent in Latin America. In Mexico, for example, there is no direct equivalent, so materials prepared in anticipation of litigation—such as investigation notes, legal analyses, or strategy documents—may not be protected from disclosure if seized or requested in legal proceedings.

Development in Mexico

A significant shift occurred in 2025 when Mexico introduced Article 77 Bis to its antitrust law. For the first time, the law instructs the Mexican antitrust authority not to seek or use communications between a company and its external counsel when those communications are for legal advice. Companies can request that these communications be excluded from proceedings, marking a major step forward for protecting legal privilege in antitrust cases.

However, Article 77 Bis has a notable limitation: It doesn’t mention communications between a company and its in-house lawyers. As a result, if a company’s legal team is internal, those conversations may not be protected.

This creates a two-tier system for multinationals operating in Mexico; communications with external counsel are shielded in antitrust cases, but those with in-house counsel remain vulnerable. Importantly, Article 77 Bis doesn’t extend to work product materials, leaving such documents potentially exposed in investigations.

The Cartel Scenario

To illustrate how these differences matter in practice, consider a scenario increasingly relevant for multinationals in Latin America: the overlap of legitimate business and cartel activity.

Suppose a US-based multinational company operates in Mexico, where certain cartels are designated as terrorist organizations under US law, making any assistance to them strictly prohibited. In Mexico, however, it is said that cartels are deeply embedded in legitimate businesses, such as logistics providers.

Imagine a multinational unknowingly using a cartel-controlled logistics company. Acting on cartel intelligence, Mexican authorities launch a sweeping investigation, raiding both companies and seizing records, computers, and communications between the multinational’s Mexican executives and in-house lawyers.

This highlights a critical gap: In the US, such communications and work product would likely be protected, unless the crime-fraud exception applied. In Mexico, and much of Latin America, the situation is far less certain.

Attorney-client privilege isn’t as robustly enforced as in the US, and in high-profile investigations involving organized crime or terrorism, authorities may feel justified in examining all seized materials—including communications with legal counsel and work product—particularly if they suspect that legal advice may have been used to facilitate or conceal criminal activity. There is no assurance that privileged communications or work product will be separated or shielded from review.

Risks for Multinationals

The disparity in privilege protections across jurisdictions creates several risks for multinational companies:

Loss of Privilege: If authorities in countries with weaker privilege protections review privileged communications or work product, the company may lose the ability to assert privilege over those materials in subsequent proceedings.

Regulatory Exposure: Seized materials may be shared with US authorities, potentially triggering further investigations or prosecutions.

Reputational Damage: Public disclosure of internal legal communications can harm a company’s reputation and erode trust with stakeholders.

Internal Tensions: In-house lawyers in countries with weaker privilege protections may be caught between their duty to protect client confidences and their obligations under local law, which may require them to report suspicious activities.

Multinational companies must adapt legal risk management to each jurisdiction, as relying on US-style protections abroad can be costly. While Mexico’s Article 77 Bis improves protection for external counsel in antitrust matters, significant gaps remain for in-house counsel and the law’s limited scope. The lack of a work product doctrine further heightens risk in Latin America.

This article does not necessarily reflect the opinion of Bloomberg Industry Group, Inc., the publisher of Bloomberg Law, Bloomberg Tax, and Bloomberg Government, or its owners.

Author Information

Nereida Meléndez is a partner at DLA Piper, specializing in investigations and enforcement actions for multinational corporations across Latin America and the Caribbean.

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