From January 3rd 2017 there is a significant step in the interpretation of the law and the sanctions that are being applied for reckless and dangerous tackles particularly to the head and neck area
In a change to law, World Rugby has redefined illegal (high) tackle categories and increased sanctions to deter high tackles via a law application guideline. This will apply at all levels of the game from 3 January 2017 introducing minimum on-field sanctions for reckless and accidental contact with the head, effectively lowering the acceptable height of the tackle.The guideline will be supported with a global education programme.

From 3 January, two new categories of dangerous tackles will carry penalty offences to deter and eradicate high tackles:

See official RFU communication including example videos

Reckless tackle

A player is deemed to have made reckless contact during a tackle or attempted tackle or during other phases of the game if in making contact, the player knew or should have known that there was a risk of making contact with the head of an opponent, but did so anyway. This sanction applies even if the tackle starts below the line of the shoulders. This type of contact also applies to grabbing and rolling or twisting around the head/neck area even if the contact starts below the line of the shoulders. Minimum sanction: Yellow card
Maximum sanction: Red card

Accidental tackle

When making contact with another player during a tackle or attempted tackle or during other phases of the game, if a player makes accidental contact with an opponent’s head, either directly or where the contact starts below the line of the shoulders, the player may still be sanctioned. This includes situations where the ball-carrier slips into the tackle.

Minimum sanction: Penalty