Listening to the Grant Wahl podcast with Howard Webb on this subject. There is some good stuff in here, and I recommend it to everyone.
We all need to bone up on how VAR works and where the shortcomings may be. This will arrive in MLS in just over 3 months, and our first game under it will be our home game against the Red Fools on August 6.
Here is a summary of how it works.
1. There are 4 types of calls that can be reviewed.
- Goals and whether there was a violation during the build up
- Penalty decisions
- Red Card decisions
- Mistaken Identity
2. The standard is a "clear and obvious error"
3. The process begins with the Video Assistant Referee (VAR) and his/her assistant reviewing the play in question on a bank of monitors. This can be triggered by the referee requesting the review or by the referee's decision at the recommendation of the VAR. The VAR can conduct a "silent review" to see if he/she should recommend a review to the referee.
4. If the VAR believes there has been clear and obvious error, he/she will contact the referee with that judgment. The referee can then either change the call on the advice of the VAR or conduct an On Field Review (OFR) by going to a designated spot on the sideline to review the video.
5. The referee is allowed to stop play to reverse a call or conduct an OFR, but it not supposed to do so when either team is engaged in an attacking chance.
6. If the referee changes a decision, he will precede that call by making a rectangle with his hands (see below) to indicate that it was changed by video review.
A few additional notes.
- Red cards are reviewable, but second yellows are not - sorry Bayern fans; Vidal's sending off would not be affected.
- Players who demand a video review by making the rectangle motion are subject to booking.
- The VAR may be in the Stadium or at another location.
- Slow motion should only be used for "point of contact" offenses, such as physical offenses and handballs. Regular speed should be used to determine the intensity of an offense and whether a handball was deliberate.
- Reviews for goals, penalty kick decisions and DOGSO red cards go back to the beginning of the "attacking possession phase" - i.e. when the attacking team first gained possession of the ball or restarted play. Other reviews only cover the incident itself.
http://quality.fifa.com/en/var/#work
http://static-3eb8.kxcdn.com/documents/216/VAR_Protocol Summary_v1.0.pdf
https://www.theguardian.com/football/2017/mar/09/video-assistant-referee-stamp-out-match-fixing