IT WAS a result that almost nobody wanted or expected. On July 8th, as the match-ending siren sounded in the third and final test of the British and Irish Lions’ tour to New Zealand, the scores were level at 15-15, meaning that the series had finished with a 1-1 tie. In their pre-tour negotiations, the organisers from both sides had made no provision for a deadlock after three full matches of 80 minutes, which left both sets of players and fans disappointed. That regulatory failure was far from the only one to elicit grumbles. Rugby’s rulebook also came under considerable scrutiny, as a number of flaws were revealed during the test matches—including a crucial one in the offside laws that effectively decided the series. The tour ought to be remembered for proving that the All Blacks are human after all, and that the Lions still make sense as a joint entity. But those lessons might be overshadowed by a more mundane one: namely, that the sport’s statutes clearly need updating.

Drawing with the Kiwis is a remarkable achievement. New Zealand are the most dominant team in rugby union’s history, and had won their last 38 matches at Auckland’s Eden Park. The Lions, a combined side of the best players in Britain and Ireland, had only three weeks and six games before the test series in which to gel. Their star power is so great that they are typically ten points per match better their strongest constituent nations. Still, the All Blacks were expected to win by that margin in any given game, and beat the Lions three-quarters of the time. They romped their way to a 30-15 victory in the opening test on June 24th. The Lions achieved a famous 24-21 upset a week after, leaving the third game poised for an epic climax.

A stalemate was little cause for celebration. These are rare even between well-matched teams. RugbyVision, a forecasting model run by Niven Winchester of MIT, reckoned there was a 3% chance of one occurring in each test. The players looked confused at the final whistle, with some anticipating an extra-time period. Another whistle never came. The captains held the trophy awkwardly between them. The fans were eerily subdued. Borrowing an old sporting adage, Steve Hansen, the All Blacks’ coach, said the draw was “like kissing your sister”.

A Lions series is second only to the Rugby World Cup: the team comes together once every four years to tour the southern hemisphere, and will not return to New Zealand until 2029. For such an important event to end without a winner would be unthinkable in other sports. Nobody would have tolerated a 0-0 draw between Germany and Argentina as the conclusion to the most recent World Cup. The National Football League’s first-touchdown-wins overtime rule might be flawed, but there would have been an uproar had the Patriots and Falcons called it quits at 28-28. Even cricket, a sport notorious for its draws, has a tiebreaking mechanism for level test-match series: the holder of the trophy retains it.

The All Blacks thumped the Lions 3-0 in 2005, and would be the obvious choice if you had to pick a winner this time. They led the aggregate score in the series 66-54, whereas the tourists were only ahead on the scoreboard for three out of 240 minutes. If you had told Lions’ fans before the tour that they would avoid defeat, they would have been delighted. But most of them were dissatisfied with parity. A poll by Sky Sports, a British broadcaster, showed that five-sixths of respondents favoured some kind of tiebreaker.

Two Rugby World Cup finals have been decided with a 20-minute extra time period, which is usually followed by ten minutes of first-score-wins and then a kicking shootout. RugbyVision estimated that the probability of this series finishing level after three tests was only 3%. Nonetheless, the omission of a tiebreaker meant that rugby’s most venerated tradition ended as an anticlimax. On current strength, such an outcome would happen 2% of the time against Australia or South Africa, the Lions’ other (and significantly weaker) opponents. That risk is not worth taking.

While the tour’s regulations prevented a satisfactory ending, a number of loopholes in the sport’s rulebook left fans complaining about the results themselves. An All Black player was sent off in the second test after connecting with an opponent’s head in a collision, an offence that carries a maximum sanction of a red card; a Lion escaped with ten minutes in the sin-bin for a similar shoulder charge. The tourists earned a match-winning penalty in the dying minutes of that game, after one of their players leapt towards a tackler while catching an errant pass and was hit in the air. Off-the-ground challenges are not allowed, but this usually applies to players collecting a high kick: there is no explicit ban on attackers jumping towards defenders, which would make any attempt to tackle them illegal. There is also no law that prevents the ball-carrier from stooping towards a tackle, which increases the risk of contact to the head. Such a challenge resulted in a yellow card for an All Black defender in the third test.

The biggest controversy was saved for the climax of the final game. With 77 minutes on the clock and the scores level, Liam Williams, a Lion (pictured, centre), jumped to catch a kicked ball and spilled it. The ball cannoned at close range into Ken Owens, one of his teammates (pictured, right), who was retreating quickly towards him. Mr Owens instinctively caught the ball before releasing it. This rapid sequence of events exposed a significant legal flaw. Law 11 states that you are offside if you are “in front of a team-mate who last played the ball”, which Mr Owens was. But his offence is governed by two clauses, neither of which has priority.

Rule 11.6 says that “when an offside player cannot avoid being touched by the ball or by a team-mate carrying it, the player is accidentally offside”, a description that matches Mr Owens’ crime. The sanction for this misdemeanour is a scrum, which offers no immediate chance to score points. But clause 11.7 requires a penalty if “a player knocks-on and an offside team-mate next plays the ball”. Slow-motion replays were inconclusive as to whether Mr Williams knocked the ball forwards. Romain Poite, the referee, judged that he had. That gave him an impossible choice. In real time he awarded a penalty under clause 11.7, which would have handed the All Blacks victory. After watching several replays, he downgraded the sentence to a scrum according to 11.6, which offered the Lions a last-minute reprieve.

Mr Poite should not have faced such a dilemma at a crucial moment in the game’s history. A similar incident marred the 2015 World Cup, when Scotland were cruelly denied an improbable win against Australia by an incorrect last-minute decision. RugbyReferee.net, a refereeing blog, has asserted that the law “needs fixing before it happens again”.

World Rugby, the sport’s governing body, has modernised the rules in recent years: the sport only turned professional in 1995, leaving it decades behind almost every other. It introduced five changes last November, and is trialling more among junior teams. Under-20 sides are currently testing new offside rules at rucks, after Italy exposed a loophole earlier this year. But it has no plans to make any further amendments at the senior level before the next World Cup in 2019. The Lions should get their tiebreaker rule before their trip to South Africa in 2021. It will come too late, however, to prevent a frustrating finale to an enthralling series.