Ireland rugby lock Tadhg Beirne was sent off early on in his side’s clash with New Zealand rugby in Chicago.

Beirne was initially shown a yellow card by referee Pierre Brousset after making head contact in an upright tackle on Beauden Barrett.

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On bunker review, the sanction was upgraded from yellow to red by foul play review officer Dan Jones, who deemed that there had been a sufficiently high level of danger.

With the 20-minute red card in place during this Quilter Nations Series, Ireland head coach Andy Farrell was able to bring on Iain Henderson.

But what are the laws around head contact that referees are following and how do they decide on the punishment? Here’s everything you need to know:

What are World Rugby’s laws on head contact?

Head-on-head contact in the tackle comes under Law 9 of the Laws of Rugby Union, which covers foul play.

Law 9.11 dictates “Players must not do anything that is reckless or dangerous to others, including leading with the elbow or forearm, or jumping into, or over, a tackler” and Law 9.13 goes on to say “A player must not tackle an opponent early, late or dangerously. Dangerous tackling includes, but is not limited to, tackling or attempting to tackle an opponent above the line of the shoulders even if the tackle starts below the line of the shoulders.”

If a player breaks these laws and the act is deemed to be reckless or dangerous, then the referee is entitled to issue a yellow or red card.

World Rugby also clarify the intent of the laws, stating in their guidelines that: “ Player welfare drives World Rugby’s decision making for zero tolerance of foul play, especially where head contact occurs. The focus must be on the actions of those involved, not the injury – the need for an HIA [a Head Injury Assessment] does not necessarily mean that there has been illegal head contact.”

What are the punishments for head-on-head contact?

Ok, this is where things get technical and debates start to occur. In March 2023, World Rugby issued their latest ‘head contact process law application guidelines’ to guide referees on whether foul play has occurred and how it should be punished.

The referee has to go through a four-step process (detailed below) to determine the extent of the foul play and the sanction. The four steps are:

1. Has head contact occurred?
2. Was there any foul play?
3. What was the degree of danger?
4. Is there any mitigation?

Step 1 (has head contact occurred?) is relatively straightforward, with head contact including the head and the face as well as the neck and throat area. If any head contact is made at all, we move on to Step 2.

Step 2 (was there foul play?) is a touch more complex. The referees are told to consider whether the head contact was either intentional, reckless or avoidable – e.g. the defender is always upright. If it was, the tackler will be penalised and they move on to Step 3. However, if the head contact was deemed not to be foul play, the game continues.

Step 3 (what was the degree of danger?) – judged from high to low – determines the initial punishment.

A degree of high danger is judged on any of: direct contact rather than indirect, a high-force impact, a lack of control from the tackler, the incident occurring at high speed, the tackler leading with the head/shoulder/elbow/forearm or the tackle being reckless. If the referee judges there to be a high degree of danger, a red card will be shown.

Meanwhile, low danger is judged as indirect contact, low force, low speed or no leading head/shoulder/forearm/swinging arm and a yellow card or even just a penalty to the opposition may be awarded.

The final step, Step 4 (is there any mitigation?) determines whether the punishment can be reduced by one grade (i.e red card down to yellow card or yellow card down to just a penalty). Mitigation includes a sudden or significant drop in height or change in direction from ball carrier, a late change in dynamics due to another player in the contact area, a clear effort from the tackler to reduce their height or the tackler having no time to adjust.

However, mitigation will never apply for intentional or always-illegal acts of foul play.

What about the Foul Play Review Officer/Bunker review?

Introduced ahead of the 2023 Men’s Rugby World Cup was the Bunker review system. This allows the referee to issue a yellow card to a player, sending them to the sin-bin while play goes on, where a Foul Play Review Official (FPRO) will then take another look at the incident and determine if the yellow card should be upgraded to red, allowing the game to continue rather than a long stoppage to debate this.

The referee crosses their arms to indicate a Bunker review will take place.

Once a player is in the sin-bin, the FPRO has up to eight minutes to review the decision and decide if it warrants upgrading to a red card. If not, the player will return to the field after their 10 minutes in the sin-bin has elapsed.

What is the 20-minute red card?

Referees will have the option to award a 20-minute red card for technical offences. Any act of foul play which is deemed not deliberate or intentional will now see the player punished with a 20-minute red card rather than the permanent sending off that would have happened before.

In these circumstances, the offending player will be removed from the field of play for the remainder of the game but their team will be able to replace that player after 20 minutes, with one of their available replacements taking the team back to 15 men.

This will stop permanent red cards being given for offences such as accidental head on head contact, where teams would be reduced to 14 men for the rest of the game.

Will there still be permanent red cards?

Yes. Wolrd Rugby have confirmed that referees will retain the ability to award a permanent red card for foul play, deemed to be deliberate and dangerous. In that instance, a traditional red card means a player can’t be replaced by their team even after 20 minutes have elapsed and the player will receive the full sanctioning, and subsequent disciplinary process.