An assessment of the World Rugby law application guidelines for the breakdown on sanctioning and player adherence

World Rugby’s law application guideline for the breakdown was developed to make the breakdown safer, fairer, and simpler to understand. The aim of this study was to use video analysis to assess the impact of these guidelines by comparing player adherence from the 2019 Rugby World Cup (pre-guidelines) to the 2020 Autumn Nations Cup (post-guidelines) as well as the rate of sanctioning by match officials. 1444 contested breakdowns were individually analysed by coding any infringement that occurred as well as the sanctioning outcome. The Rate Ratios (RR), 95% Confidence Interval (CI) and probability (p) values were calculated to compare proportions before (pre) and after (post) the law application guidelines. No change in the rate of infringements was observed (RR =1.04; 95% CI =0.98-1.11; p =0.188), though the rate of infringements penalised increased (RR =1.54; 95% CI =1.19-1.99; p =0.001). Reductions in the rate of two of the five offences targeted by the guidelines were observed; “offside” (RR =0.60; 95% CI =0.41-0.87; p =0.008) and “remains on feet” (RR =0.15; 95% CI =0.08-0.28; p <0.001). All dangerous play infringements reduced; “charged in” (RR =0.26; 95% CI =0.14-0.47; p <0.001), “contact above shoulder” (RR =0.20; 95% CI =0.11-0.35; p <0.001), “intentional collapse” (RR =0.04; 95% CI =0.00-0.63; p =0.023). Despite no significant reduction in the rate of total infringements between the tournaments, the reduction in the rate of dangerous play offences show a potential shift in player behaviour surrounding attitudes towards head injuries. Further, the accuracy of referee decision making did improve, suggesting that the law application guideline was successful in providing a clearer picture for match officials, which should lead to more uniform refereeing at the elite level of the sport.