Forensic certification of time clocks and attendance records

Forensic certification of time clocks is a technical review, carried out with forensic methods, of the systems a company uses to record staff attendance and working hours: biometric clocks, terminals, apps and databases. The goal is for those records to be reliable and to hold up as evidence if a labor dispute arises. Castro Defense offers this service to employers across Mexico, including foreign-owned manufacturers and subsidiaries operating under Mexican labor law.

It is an independent digital forensics service. It is not an official certification by the Ministry of Labor and Social Welfare (STPS) or any other authority.

Why your records matter in a labor dispute

Mexico’s Federal Labor Law (Ley Federal del Trabajo, LFT) places much of the burden of proof on working time on the employer:

• Burden of proof. In a dispute, the employer must prove, among other facts, absences and regular and overtime hours when overtime does not exceed nine hours a week (art. 784).
• Retention. It must keep the attendance records used at the workplace for the last year of employment and one year after (art. 804).
• Presumption. If it does not produce them in court, the facts the worker states about them are presumed true unless proven otherwise (art. 805).
• Electronic evidence. To assess a digital document, the court appoints experts to determine whether the information is intact and unaltered as generated, and to place it in time and space. If a party holding the document does not make it available to the experts, the other party’s statements about it are presumed true (art. 836-D).

The new electronic recording duty

The amendment published in Mexico’s official gazette on May 1, 2026 added to the LFT a duty to record each worker’s hours electronically, with start and end times, and to provide the records to the authority on request (art. 132, section XXXIV):

• The STPS will issue rules defining who it applies to and any exceptions; they take effect on January 1, 2027.
• The content of the electronic record is full proof if it is shown to have been agreed between worker and employer.
• Non-compliance is punishable by a fine of 250 to 5,000 times the UMA (art. 994, section IV Bis).

The same amendment gradually reduces the maximum working week from 48 hours in 2026 to 40 in 2030. A reliable recording system is the foundation for showing that your company complies.

What does the forensic certification review?

• Inventory. Devices, software, databases and who administers them.
• Time. Each device’s time source and synchronization, to detect drift.
• Identity. How each punch is linked to a person: fingerprint, face, badge or password.
• Integrity. Logs, edit permissions, change history and backups: who can modify a record and whether a trace remains.
• Export and preservation. How to extract records with hash values and chain of custody for use in court.
• Procedures. Internal policies and how staff are informed about and accept the recording system.

Findings are reported as found, including weaknesses, together with recommendations to fix them. Processing staff data, including biometrics, must also comply with Mexico’s Federal Law on the Protection of Personal Data Held by Private Parties.

How does it work?

1. Initial consultation. Number of workplaces, headcount and systems in use.
2. Technical survey. Review of devices, configuration and databases. Format: remote, on-site or both.
3. Testing. Time synchronization, record integrity and access controls.
4. Report. Findings, risks and recommendations.
5. Support if a dispute arises. Preservation of records with chain of custody and, where appropriate, an expert report.

Deliverables: technical report, expert report signed by a perito, certificate of review. Recommended frequency and validity: frequency and validity of the review. Expert’s credentials: degrees, professional license and forensic certifications.

What this service does not do

• It does not replace STPS rules or inspections.
• It does not modify or “fix” records: it documents their condition and integrity.
• It does not guarantee the outcome of a labor case, which depends on all the evidence and the court’s decision.

Request a review

Tell us how many workplaces you have and which recording system you use.

This content is for information only and is not legal advice for a specific case. The outcome of any proceeding depends on the facts, the evidence and the authority’s decision; Castro Defense does not guarantee results.

Official sources

• Federal Labor Law (Ley Federal del Trabajo), arts. 132 section XXXIV, 784, 804, 805, 836-D and 994 section IV Bis, and transitional provisions of the decree published in the DOF on May 1, 2026. Chamber of Deputies (Spanish).
• Ministry of Labor and Social Welfare (STPS). Government of Mexico (Spanish).

Frequently asked questions

Is electronic time recording mandatory in Mexico?

Yes. The Federal Labor Law amendment published on May 1, 2026 requires employers to record each worker's hours electronically, including start and end times, and to provide the records to the authority on request (art. 132, section XXXIV). The Labor Ministry's rules on scope and exceptions take effect on January 1, 2027.

What happens if a company does not comply?

The law sets a fine of 250 to 5,000 times the Unit of Measure and Update (UMA) for employers that fail to comply (art. 994, section IV Bis). In addition, if an employer does not produce its attendance records in court, the facts the worker states about them are presumed true unless proven otherwise (art. 805).

Are time clock records valid evidence in a Mexican labor case?

They can be. To assess a digital document, the labor court appoints experts to determine whether the information is intact and unaltered as generated (art. 836-D). And the content of the electronic time record is full proof if it is shown to have been agreed between worker and employer (art. 132, section XXXIV).

Is this certification issued by the Labor Ministry?

No. It is an independent forensic technical review of the integrity and reliability of your system. It does not replace the labor authority's rules or inspections.

How long must attendance records be kept?

The Federal Labor Law requires employers to keep the attendance records used at the workplace for the last year of employment and one year after it ends (art. 804).