Digital evidence in judicial proceedings: issues of validity and authenticity

Digital evidence in judicial proceedings: issues of validity and authenticity

Digital evidence has become a central element in most modern disputes. An email, a WhatsApp message, a system access log, or a social media post can be decisive in proving facts, intent, or breaches. However, the mere existence of an electronic trace does not mean it will automatically qualify as strong evidence in court.

In judicial proceedings, digital evidence often faces two major challenges: its validity, understood as admissibility and lawfulness, and its authenticity, which requires proving that the content is genuine, has not been altered, and can be attributed to a specific person or source. For this reason, understanding what types of digital evidence exist, how they should be preserved and how authenticity is assessed is essential to avoid challenges and strengthen evidentiary value.

Types of digital evidence

First, it is useful to distinguish the main types of digital evidence:

• The most common are electronic communications, such as emails, instant messaging, and social media messages, which are often submitted to prove agreements, warnings, claims, or conduct.
• Digital documents and files are also frequently used, including electronically signed contracts, PDFs, spreadsheets, or cloud-stored documents, whose evidentiary weight is reinforced when they are submitted in their original format and with metadata preserved.
• Another important category is web and social media content, such as posts, advertisements, reviews, or web pages, where the main issue is volatility, since content can be easily modified or deleted.
• Added to this are technical records or logs, which include server traces, system audits, access records, IP addresses, and activity logs, particularly useful in cybersecurity matters or technology-related contractual breaches.
• Audio, video and digital images are also commonly produced as evidence, including recordings, CCTV footage, screenshots, or photographs, whose assessment is often more delicate due to the possibility of cuts, edits, or lack of continuity.
• Finally, there are more advanced forms of evidence, such as time stamping, digital custody systems or records linked to connected devices, which can provide additional guarantees when they have been properly obtained and documented.

Preservation and custody of evidence

However, the factor that most strongly determines the strength of any digital evidence is its preservation and custody. In the electronic context, custody involves maintaining the integrity and traceability of the evidence from the moment it is obtained until it is presented in court. If it cannot be coherently explained who obtained it, when, from which device or account, how it was preserved, and what measures were taken to prevent alterations, the opposing party will often question its reliability.

Many problems arise when only screenshots are submitted without further support, when a device or file is manipulated without documentation, or when the origin trail is lost. For example, a screenshot of a conversation may be enough to frame the dispute, but it is more vulnerable if it is not accompanied by a complete export, the original file, or technical verification.

Proper custody, by contrast, aims to preserve the original or a faithful copy, minimize interventions on the evidence, document the collection and preservation process, and, when the case requires it, apply technical safeguards such as generating digital fingerprints (hash values) or time stamping.

In practice, the higher the risk of challenge or the greater the importance of the fact to be proven, the more advisable it is to adopt measures that demonstrate the evidence remained intact and that there were no reasonable opportunities for manipulation.

How is the authenticity of electronic evidence assessed?

The authenticity of electronic evidence is typically assessed on the basis of three essential issues:

1. The first is attribution, meaning whether the evidence can be linked to the person who allegedly created or sent it. It is not enough for a name to appear on a screen; what matters is proving the relationship between the account or device and the individual, relying on contextual data, the coherence of the conversation, email header information, authentication records, or other elements that consistently identify the user.
2. The second issue is integrity: the court must be able to trust that the content has not been modified since its creation. For this purpose, the original formats, metadata, the absence of signs of editing, and technical and chronological consistency are particularly important, as well as, where available, verification through hash values, time stamping, or third-party custody.
3. The third issue is the reliability of the method of collection and presentation. If the procedure used to capture or extract the evidence is weak or insufficiently transparent, authenticity is undermined. Conversely, when evidence is provided in full, the method of collection is explained, and a forensic IT expert report is submitted in complex cases, the evidence tends to become more robust and better able to withstand adversarial scrutiny.

Ultimately, digital evidence is extremely useful, but also fragile. Its success in court depends not only on what the document or message “shows,” but on the ability to prove that it is lawful, intact and attributable.

Anyone preparing proceedings with a technological component should anticipate the usual risks by preserving evidence early, ensuring proper custody, and, where the dispute requires it, relying on technical verification and expert evidence. This reduces challenges and increases the credibility of the evidence before the court.