It's a little known fact that video replay in football has already begun its entrance into the sport, at least in experimental stages. The NCAA recently approved it, and the MLS was testing it in a youth tournament. However there seems to be a dearth of knowledge on how it is actually implemented during the play of the game. While a few places give suggestions on how it could, no one seems to know what exactly the official procedure is, which should at least be known from the MLS test.
Here's a link to an article regarding it's first use in competitive play. The official procedure right now appears to be:
The VAR (video assistant referee) automatically reviews every goal, every red card and all penalties, and communicates directly with the head referee, who ultimately decides whether to resort to the monitor.
It appears that behind each goal is a small monitor for the referee to make a quick review of the play if they so choose. The last I heard regarding full implementation in MLS, is that Don Garber (MLS commissioner) is hoping for it to be used starting in the second half of the 2017 season.
IFAB's VAR Protocol clearly defines how Video Assistant Referee technology needs to be implemented. Here is the Principle section of the protocol:
The use of VARs in football matches is based on a number of principles, all of which must apply in every match using VARs.
A video assistant referee (VAR) is a match official, with independent access to match footage, who may assist the referee only in the event of a ‘clear and obvious error’ or ‘serious missed incident’ in relation to:
- a. Goal/no goal
- b. Penalty/no penalty
- c. Direct red card (not second yellow card/caution)
- d. Mistaken identity (when the referee cautions or sends off the wrong player of the offending team)
The referee must always make a decision, i.e. the referee is not permitted to give ‘no decision’ and then use the VAR to make the decision; a decision to allow play to continue after an alleged offence can be reviewed.
The original decision given by the referee will not be changed unless the video review clearly shows that the decision was a 'clear and obvious error'.
Only the referee can initiate a ‘review’; the VAR (and other match officials) can only recommend a ‘review’ to the referee.
The final decision is always taken by the referee, either based on information from the VAR or after the referee has undertaken an ‘on-field review’ (OFR).
There is no time limit for the review process as accuracy is more important than speed.
The players and team officials must not surround the referee or attempt to influence if a decision is reviewed, the review process or the final decision.
The referee must remain ‘visible’ during the review process to ensure transparency.
If play continues after an incident which is then reviewed, any disciplinary action taken/required during the post-incident period is not cancelled, even if the original decision is changed (except a caution/sendoff for stopping a promising attack or DOGSO).
If play has stopped and been restarted, the referee may not undertake a ‘review’ except for a case of mistaken identity or for a potential sending-off offence relating to violent conduct, spitting, biting or extremely offensive, insulting and/or abusive gesture(s).
The period of play before and after an incident that can be reviewed is determined by the Laws of the Game and VAR protocol.
As the VAR will automatically ‘check’ every situation/decision, there is no need for coaches or players to request a ‘review’.
Here is how VAR was implemented during the FIFA World Cup 2018:
The same 4 incidents were reviewable as defined in VAR protocol. Then:
STEP 1 - Incident occurs
The referee informs the VAR, or the VAR recommends to the referee that a decision/incident should be reviewed.
STEP 2 - Review and advice by the VAR
The video footage is reviewed by the VAR, who advises the referee via headset what the video shows.
STEP 3 - Decision or action is taken
The referee decides to review the video footage on the side of the field of play before taking the appropriate action/decision, or the referee accepts the information from the VAR and takes the appropriate action/decision