In the days following the January 2021 attack on the US Capitol, many private individuals acted as digital researchers in attempts to identify suspected riot participants, analysing videos, photographs and cell-phone data. These crowd-sourced investigations complemented rather than replaced formal police investigations. While this is an example of private investigations supporting law enforcement, the digital call to join the armed Capitol riot illustrates the opposite dynamic which resulted in multiple deaths and injuries.

Once upon a time in the digital West

The investigations and the call to join the riot are both examples of a growing phenomenon, ‘digital vigilantism’ (DV): citizens use digital media to investigate alleged wrongdoings and impose informal punishment outside formal justice. Common examples are acts of cultural violence, breaches of social protocol, unwanted visibility through the dissemination of private information (doxxing), and online harassment.

Punishments that result from DV may also manifest outside the digital realm through physical harassment, riots, and even terrorist acts, as demonstrated by the Capitol riot. Unlike ordinary online criticism, which is an essential aspect of the democratic process, DV consists of acts of punishment outside formal justice that are inspired by online communities and move beyond mere disagreement in public debate.

This raises an important question: to what degree can public participation strengthen justice, and when does it undermine the rule of law? I argue that DV reflects the growing perception that citizens can administer justice themselves. Its perceived legitimacy is very different from formal legal legitimacy.

Perceived legitimacy versus legal legitimacy

One of the crucial arguments in the defence of DV has been the framing of corresponding actions as ‘bottom-up policing.’ This argument assumes that ordinary citizens should play a greater role in administering justice. Simultaneously, this logic denies states the monopoly of violence and justifies violent vigilant actions.

A possible explanation for these developments may be found in the decentralisation and deputisation of citizens through (neo-)liberal politics from around the 1960s onwards. Political trends like these have made citizens increasingly responsible for their own security and the social order in general. Consequently, these developments have resulted in a shift away from top-down systems of social organisation and governance. This means that DV is justified within ‘executing groups’ as it allegedly allows more people to directly participate in the administration of justice. Such shifts in the social perception of sentencing legitimacy (for example who should administer justice and how) can strongly be linked to the rise of DV.

Challenges to the criminal justice systems

DV poses many challenges to criminal justice systems beyond immediate illegal practices. It legitimises punishment within online communities while ignoring real-world consequences. This creates tension as police investigations may rely on public input while the circulation of case-specific information may in turn evoke acts of DV. For example, in the aftermath of the Capitol riot private investigations may have helped to identify offenders, but punishment then exceeded formal justice, as participants were named and shamed, fired from their jobs, and publicly ostracised.

Moreover, while DV actions are defended on a strong moral basis within the executing groups, these justifications do not always match commonly recognised moral principles. This lack of moral consistency results in arbitrary executions of informal justice while digital vigilantes claim that they represent public opinion. This creates a lack of clear distinction between formal moral principles of justice and those of DV, since both claim to represent common moral norms. This ambiguity can then be politically exploited by populist parties who seek to threaten the rule of law.

When public participation undermines due process

Unlike during the 19th century gold rush where there was often no regulation or state law, digital vigilantism now operates alongside functioning criminal justice systems and risks undermining the rule of law. It is vital that we uphold and strengthen the legitimacy of criminal justice systems in the digital world. To achieve this, criminal justice systems need to align with public perception through transparency, consistency in application, and sensitivity to all parties involved through effective communication. Often, such factors are tied to national and international laws. In the EU, for example, the Digital Services Act (DSA) requires large online platforms to meet transparency, due diligence and risk-assessment obligations.

Nonetheless, DV may signal areas where cyber law is still lacking and requires expansion or adaptation. Any reforms should be implemented through due process and by balancing the power of the law with the protection of individual rights. In particular, it is vital to refine legal mechanisms that serve to protect against online harassment and the spread of private information. It may be time to saddle up and appoint legal legitimacy and the rule of law as the new sheriffs of the digital Wild West.