Australia’s National Rugby Championship could play a key role in testing major law amendments to the union code, including a reduction in legal tackle height to the waist.

Six law amendments have been approved for closed trials by World Rugby’s executive committee following a major review.

These include reducing tackle height to the waist and high tackle technique warnings. A high tackle warning system has operated at the last two World Rugby Under-20 Championships.

World Rugby say their reduced tackle height rationale is that forcing players to tackle lower may reduce the risk of head injuries to both the tackler and tackled player.

Other trialled amendments will see reviewing of a yellow card when a player is in the sin-bin, aimed at ensuring players who are guilty of serious foul play do not escape with a yellow card when they deserved red.

There is also the introduction of an infringement (penalty and free-kick) limit for teams. Once a team has reached the limit, a mandatory yellow card is given to the last offending player as a team sanction.

And a 50:22 kick will see a team in possession that kicks the ball from inside their own half indirectly into touch inside their opponents’ 22 – or from inside their own 22 into their opponents’ half – gain a throw-in to the resulting lineout.

A number of unions have expressed their interest in operating one or more of the approved trials in their domestic or cross-border competitions, including Rugby Australia in the National Championship this year.

World Rugby says other unions could stage trials, including the French Federation at all community levels, plus South Africa for the Currie Cup and domestic leagues in Georgia and Fiji.

“The package of trials will be rolled out as designated closed trials in competitions around the world,” World Rugby said in a statement.

Initial closed trials could start later this year, with reviews taking place throughout 2020. Any northern hemisphere global trials would start in August 2021.

In addition to approved trials, the executive committee has rubber-stamped moves for further analysis of areas such as reducing the number of permitted substitutions and players being off their feet at a ruck.

“World Rugby is unwavering in its commitment to ensuring rugby is as simple and safe to play as possible for all,” chairman Bill Beaumont said.

“While injury incidence in the sport is not increasing and concussion incidence is decreasing, we can and must do more to reduce injuries at all levels. This is an important milestone on that journey.

“The next step is to identify in partnership with our unions’ appropriate competitions to run the trials.”