The Covid era has forced the ICC to use umpires from host countries for international matches since the middle of last year. This has given occasion for old notions about the neutrality in umpiring to be aired.

Where possible, the home umpires used during the last year have been from the ICC's Elite Panel. Elsewhere, they have been chosen from the ICC's International Panel of umpires, which includes the four top umpires from each country. (Note: the figures used for the Covid-era Tests involving home umpires in this article include 41 out of 48 Tests played, starting with England vs West Indies in Southampton in July 2020, to India vs New Zealand in Kanpur in November 2021. Seven Tests during this period featured at least one third-country umpire and have been excluded.)

Despite the existence of the DRS and a mature ICC system for developing and evaluating umpires, the wisdom of using neutral umpires has not been seriously challenged in this century.

Former ICC Elite umpire Simon Taufel was asked in 2012 by the podcaster Subash Jayaraman why neutrality was required if Test umpires were chosen from the Elite Panel. Taufel said that it was important to recognise that all umpires were neutral, and they needed to be to meet the level of performance scrutiny placed on them by the ICC. But then, he continued, "the perception of neutrality is just as important as the factual reality of neutrality. "[I]f people perceive that an umpire is a poor communicator or a poor decision-maker, regardless of the facts, he is." Not only did bringing in neutral umpires create the desired perception of neutrality, he said, it also protected umpires when they made a mistake, by removing partisanship as a possible motive.

The remarkable thing about Covid-era Tests has been the near total absence of umpiring controversies. The DRS has taken much of the sting out of umpiring decisions. While there continue to be journalists, ex-players and commentators who are still not entirely clear about the workings of the review system, there is negligible uncertainty about umpiring decisions. The natural urge of partisans to complain has tended to focus on imagined errors of process. On the face of it, this seems to prove Taufel's point about the importance of perception. I suggest that it shows that partisans will find something to complain about no matter what the process might be, and no matter what the facts.

The real stars of the show have been the umpires (and the DRS). And it is their results that drive the case for getting rid of the neutrality requirement, at least for Test cricket.

Let's consider two sets of Tests. First, the 41 matches that have featured home umpires in 2020 and 2021. The home team won 19 and lost 12 of these. Second, consider the 48 Tests from the start of 2019 to the last Test featuring neutral umpires before the enforced break due to the pandemic. The home side won 29 and lost 13 of these.

Reviews can be requested by either the batter or the bowling side, so there are four distinct types of reviewers (home and away, batting and bowling). Note that for the Tests involving home umpires, the maximum number of unsuccessful player reviews per team was increased to three per innings. This change was made because not all home umpires are Elite Panel umpires.

In the last 48 Tests featuring neutral umpires, 33% of all player reviews were upheld (50% were struck down, and 16% were struck down as umpire's call). In the 41 Tests featuring home umpires, 27% of all player reviews were upheld (53% were struck down, 20% were struck down as umpire's call).

In the home-umpires Tests, 96 of 243 (40%) of reviews by batters have been upheld, while the corresponding figure under neutral umpires is 83 out of 208 (41%). For bowlers, 56 of 324 (17%) reviews were upheld under home umpires, while under neutral umpires 53 of 209 (25%) were upheld.

Before home umpires, 25 of 96 (26%) of the reviews requested by home batters were struck down as umpire's call, while 25 of 147 (17%) of reviews requested by visiting batters were struck down that way. On the bowling side, 29 of 168 (17%) of reviews by home bowlers were struck down as umpire's call under neutral umpires, while for visiting bowlers the figure was 34 out of 156 (22%). This evidence does not support what appears to be a widely held suspicion that umpire's calls tend to go the home team's way.

This does not suggest that home umpires have been better than neutral umpires. The availability of the extra review has had its effect: bowlers requested 7.7 reviews per match under home umpires and 4.4 under neutral umpires. On the batting side, the number of reviews sought went up from 4.2 per match under neutral umpires to 5.9 under home umpires. Many of these extra reviews were taken in hope rather than expectation.

Home batters had 34% (32 of 96) player reviews upheld under home umpires, to 44% (64 of 147) for visiting batters. Under neutral umpires, the gap not only narrows (42 of 95, or 44%, for home batters; 41 of 108, or 38%, for visiting batters), the positions reverse.

This appears to be striking, though the change is relatively minor when two further factors are considered. First, an extra review was available under home umpires, so in theory, players were less selective when taking reviews under home umpires than they were under neutral umpires. While this affects both sides equally, it does mean that success rates for reviews can be expected to fall. Second, home teams were more successful in the neutral-umpires period under consideration here than they have been in Tests during the home-umpires period. Overall, under DRS, teams that lose tend to have fewer successful reviews (455 out of 1813, or 25%) than teams that win (485 out of 1605, or 30%).

This pattern is not evident when considering reviews by the bowling side under home umpires. Home bowlers had 18% of their reviews upheld (31 of 168) and away bowlers 16% (25 of 156); so both categories fare equally terribly.

The biggest skew against home batters is found in England, where 20 of 44 reviews requested by visiting batters against home umpires were successful, while only 9 of 32 reviews requested by home batters were. Under neutral umpires, the positions are reversed - 10 of 20 successful reviews by home batters, to 7 of 22 by visiting batters.

In the West Indies, under West Indian umpires, visiting batters were successful in 8 of 15 player reviews, to 8 of 21 for home batters. Under neutral umpires, the home batters successfully reviewed 7 of 11 decisions, while visiting batters successfully reviewed 5 of 10.

In Australia, under Australian umpires, visiting batters were successful in 4 out of 10 reviews, to 4 out of 17 for home batters. Note that Australia lost the only home series they played at home during this period. Under neutral umpires, Australian batters requested reviews only six times and were successful once, while visiting batters managed 6 out of 20. In the 2018-19 and 2019-20 home seasons, Australia won all but one series.

In India, under Indian umpires, home batters were successful in seven out of 18 reviews, and visiting batters in nine out of 29. Under neutral umpires, home batters successfully reviewed 2 out of 7, while visiting batters successfully reviewed 4 out of 12.

The story is similar in New Zealand, Sri Lanka, South Africa and other venues. Umpires are not biased, and their decisions are roughly equally good whether they stand as neutral umpires or as home umpires.

These figures can also be considered as follows. Home teams batted in 81 team innings (162 unsuccessful reviews available) in the 48 Tests in the neutral-umpires period, and lost 656 wickets. Visiting teams batted in 89 team innings (178 unsuccessful reviews available) in those 48 Tests, and lost 819 wickets. Home teams batted in 71 team innings (213) in the 41 Tests under home umpires, and lost 596 wickets. Visiting teams batted in 78 innings (234) and lost 688 wickets.

The figures suggest that teams were nowhere near approaching the limits of the number of reviews available to them. The closest we got to the limits was when the visitors were batting under home umpires, when 166 out of a possible 468 unsuccessful reviews were used up.

Leaving aside the umpire's-call outcomes, we can use the numbers of reviews upheld to estimate how much each side benefited under each umpiring regime by umpiring mistakes. Under home umpires, the visitors reversed 89 on-field decisions using player reviews, while the hosts reversed 63. Under neutral umpires, the visitors reversed 57 on-field decisions and the hosts reversed 79. The net benefit to the home team under home umpires is 26 dismissals over 41 Tests. Under neutral umpires the net benefit has gone to the visitors: 22 dismissals over 48 Tests.

The overall effect comes to about half a dismissal per Test match either way. Taken together with the fact that teams have tended not to get anywhere near the limit of available reviews, the evidence does not support conjecture that umpires are biased. Home umpires are no more biased for the home team than neutral umpires are biased against the home team.

If we consider the figures by umpire, then we find that the umpires outside the Elite Panel are not significantly worse performers than those on it.

The evidence is sufficiently compelling for reasonable and fair-minded observers of cricket to never have to entertain suspicions about the loyalties of umpires when the odd decision goes against the team they support. The evidence also suggests that given the support of DRS, they should have few worries about the competence of the umpires on the International Panel or the Elite Panel.

It is worth keeping in mind that these are just the decisions that were reviewed. The overwhelming majority of umpiring decisions (here I restrict umpiring decisions to responses to appeals) are not reviewed, though a review might be available. In the 41 Tests involving home umpires during the Covid era, there have been eight unsuccessful reviews per match on average, out of a possible 24 over four innings.

On the first two days of India's first Test against New Zealand in Kanpur, there were five successful reversals by batters - three by Tom Latham alone, and two by India batters. All five involved a question of thin edges - which suggested that there must be something peculiar about the ground that made it difficult for umpires to pick up thin snicks there. This is not evidence of bias. It is not even evidence of incompetence, but rather, of an interesting difficulty. Nitin Menon and Virender Sharma are terrific umpires, as the figures for the Tests in India during the Covid period show.

The ICC should consider doing away with the neutrality requirement once things get back to normal, and use any Elite Panel umpire regardless of nationality in any Test. This will probably make for easier scheduling as well. The evidence demands that umpires be trusted, and be seen to be trusted. Insisting on neutral umpires at this point is little more than giving in to the worst, most poisonous, variety of partisanship. A great sport should not give in to these tendencies.

Kartikeya Date writes the blog A Cricketing View. @cricketingview