On 5 October 2024, Liverpool played Tottenham Hotspur at the Tottenham Hotspur Stadium. In the 34th minute, Liverpool's Luis Díaz ran onto a through ball and slotted it past the goalkeeper. The linesman raised his flag for offside. The VAR team checked the decision, confirmed it was offside, and play resumed. Except Díaz was not offside. The VAR officials had misunderstood the on-field decision and thought the goal had been given, when in fact it had been ruled out. By the time they realised the mistake, play had restarted, and the goal could not be awarded. Liverpool lost 2–1, and the error dominated headlines for weeks. It was the most high-profile VAR failure in Premier League history, and it crystallised the frustration many fans feel about a system that was supposed to eliminate mistakes, not create new ones. Here is how VAR works, what it can and cannot do, and why it remains so controversial.

What VAR Is

Video Assistant Referee (VAR) is a system that uses video technology to help referees make more accurate decisions. It was introduced by the International Football Association Board (IFAB) in 2018 and has since been adopted by most major leagues and competitions, including the Premier League (from 2019–20), La Liga, Serie A, the Bundesliga, and the Champions League.

VAR does not replace the on-field referee. Instead, it acts as a safety net, checking for clear errors in four specific types of incident:

  1. Goals (and the build-up to goals)
  2. Penalties (awarded or not awarded)
  3. Red cards (direct red cards only, not second yellows)
  4. Mistaken identity (when the referee sends off or books the wrong player)

VAR cannot intervene for anything else — not for yellow cards, not for fouls outside the penalty area (unless they lead to a goal or red card), not for throw-ins or corners. The idea is to correct clear and obvious errors without re-refereeing the entire match.

How VAR Works

VAR operates from a video operations room, usually located at a central hub away from the stadium. The VAR team consists of:

  • The Video Assistant Referee (VAR) — the lead official who reviews incidents and communicates with the on-field referee
  • The Assistant VAR (AVAR) — supports the VAR and checks different camera angles
  • A replay operator — controls the video feeds and selects camera angles

The VAR team has access to multiple camera angles (typically 30–40 in the Premier League) and can review incidents in real time, slow motion, and freeze frame. For offside decisions, they use semi-automated offside technology (more on that below).

The VAR process

When a reviewable incident occurs, the VAR team checks it while play continues. If the VAR believes there has been a clear and obvious error, they communicate with the on-field referee via headset. The referee then has three options:

  1. Accept the VAR's recommendation without reviewing the footage (common for factual decisions like offside).
  2. Review the footage on the pitch-side monitor (the Referee Review Area, or RRA) and make the final decision (common for subjective decisions like handball or fouls).
  3. Reject the VAR's recommendation and stick with the original decision (rare, but it can happen).

The on-field referee always makes the final decision. VAR can only recommend a review, not overrule the referee.

The 'clear and obvious error' threshold

This is the most contentious part of VAR. The system is only supposed to intervene when the on-field referee has made a clear and obvious error — not when the decision is debatable or marginal.

For factual decisions (like offside or whether the ball crossed the line), the threshold is objective: either the player was offside or they were not. For subjective decisions (like whether a foul was a penalty, or whether a handball was deliberate), the threshold is much harder to define. What counts as "clear and obvious" to one person may not to another.

This has led to inconsistency. Some VAR interventions seem trivial (overturning a goal for a minor foul in the build-up), while others seem obvious but are not given (a clear penalty waved away because it is not "clear and obvious" enough).

Semi-Automated Offside Technology

Offside decisions are the most common VAR intervention, and they use semi-automated offside technology (SAOT), introduced in the Premier League in 2024–25.

SAOT uses 12 cameras positioned around the stadium, each tracking 29 body points on every player (head, shoulders, arms, legs, etc.) at 50 frames per second. When a pass is made, the system calculates whether any part of the attacker's body that can legally score a goal (head, torso, legs — not arms) is ahead of the second-last defender.

The system generates a 3D offside line and an animated graphic showing the player's position at the moment the ball was played. This is displayed on stadium screens and broadcast to viewers.

SAOT is faster and more accurate than manual offside checks, reducing the average VAR offside decision from 70 seconds to around 25 seconds. But it is not perfect. The system's accuracy depends on the frame rate (50 fps means there is a margin of error of up to 13 cm, according to IFAB), and the definition of "the moment the ball was played" can be subjective.

What VAR Has Changed

Fewer incorrect decisions

VAR has reduced the number of incorrect decisions. According to the Premier League, the accuracy of key match decisions (goals, penalties, red cards) improved from 82% before VAR to 96% with VAR in the 2023–24 season.

However, this does not account for the new errors VAR has introduced (like the Díaz offside mistake) or the subjective decisions where "correct" is a matter of opinion.

More stoppage time

VAR has increased the average stoppage time in Premier League matches. In the 2023–24 season, the average stoppage time was 11 minutes per match (up from 7–8 minutes before VAR), largely due to VAR checks and the time added for injuries and time-wasting.

Disrupted flow

VAR checks disrupt the flow of the game. Goals are no longer celebrated immediately, because fans and players wait to see if VAR will intervene. The delay between an incident and the final decision can be several minutes, killing the spontaneity and emotion that make football compelling.

More penalties

VAR has led to more penalties being awarded, particularly for handball and fouls that the on-field referee missed. In the 2019–20 season (VAR's first in the Premier League), 124 penalties were awarded, up from 103 the previous season. The number has since stabilised, but VAR has made referees more cautious about missing penalties.

The Controversies

VAR has been controversial since its introduction, and the criticisms fall into several categories:

1. Inconsistency

VAR is supposed to correct clear and obvious errors, but the threshold is applied inconsistently. Some decisions are overturned for minor infractions, while others that look like clear errors are not reviewed. This has led to accusations of bias and incompetence.

2. Subjectivity

For subjective decisions (handball, fouls, red cards), VAR has not eliminated debate — it has just moved it from the referee to the VAR official. Fans, players, and pundits still disagree about whether a decision was correct, and VAR has added a new layer of controversy.

3. Lack of transparency

VAR decisions are made behind closed doors, and the audio between the VAR team and the on-field referee is not broadcast live (unlike in rugby or cricket). This has fuelled conspiracy theories and mistrust. The Premier League has started releasing VAR audio after matches, but fans want real-time transparency.

4. Offside pedantry

VAR has led to goals being ruled out for marginal offsides — a player's armpit or toe being a few centimetres ahead of the defender. Critics argue this is against the spirit of the offside law, which was designed to prevent goal-hanging, not to penalise players for being millimetres ahead.

IFAB has proposed introducing offside tolerance zones (a margin of error of 5–10 cm) to reduce the number of marginal offsides, but this has not been implemented.

5. Human error

VAR is operated by humans, and humans make mistakes. The Díaz offside error at Tottenham was caused by a miscommunication between the VAR team and the on-field referee. Other errors have included VAR officials failing to spot clear fouls or drawing offside lines incorrectly.

Fan and Player Reactions

Fans, players, and managers remain deeply divided on VAR.

Supporters argue that VAR has made the game fairer by correcting clear errors that would have stood before. They point to the improved accuracy of decisions and the reduction in match-changing mistakes.

Critics argue that VAR has ruined the spontaneity and emotion of football, that it is applied inconsistently, and that it has introduced new errors while failing to eliminate old ones. They want VAR scrapped or radically reformed.

A 2023 survey by the Football Supporters' Association found that 67% of fans wanted VAR to be scrapped or significantly changed. Only 19% were satisfied with how it was being used.

Players and managers are similarly divided. Some, like Manchester City manager Pep Guardiola, have praised VAR for improving accuracy. Others, like Wolverhampton Wanderers (who proposed a motion to scrap VAR in 2024, which was voted down by other Premier League clubs), have called for it to be abolished.

Proposed Reforms

Several reforms have been proposed to improve VAR:

  1. Live audio — Broadcast the conversation between the VAR team and the on-field referee in real time, as in rugby.
  2. Offside tolerance zones — Introduce a margin of error (5–10 cm) to reduce marginal offsides.
  3. Limit interventions — Raise the threshold for "clear and obvious error" to reduce the number of trivial interventions.
  4. Challenge system — Allow each team one or two VAR challenges per match, as in tennis or cricket.
  5. Better training — Improve the training and accountability of VAR officials to reduce errors and inconsistency.

IFAB and the Premier League are considering some of these reforms, but no major changes have been implemented yet.

The Bottom Line

VAR can only intervene for goals, penalties, red cards, and mistaken identity, and only when there has been a clear and obvious error. The on-field referee makes the final decision after reviewing footage on the pitch-side monitor or accepting the VAR's recommendation. Offside decisions use semi-automated technology with 12 cameras tracking 29 body points, but the system has a margin of error and the 'clear and obvious' threshold is subjective. VAR has reduced the number of incorrect decisions from 18% to 4% in the Premier League, but it has increased stoppage time, disrupted the flow of matches, and introduced new errors. Fans, players, and managers remain divided: some say VAR improves accuracy and fairness, others say it has ruined the spontaneity and emotion of the game. Proposed reforms include live audio, offside tolerance zones, and a challenge system, but VAR's future remains contested. The technology was meant to eliminate controversy, but it has become football's most divisive innovation.