The evidence suggests Serena Williams is not being discriminated against by drug testers

Serena Williams is a well-known advocate for “clean sport”. For any athlete to be effective in such a role, it is important to comprehend how anti-doping programs work. Misunderstandings of the drug-testing process can lead to misperceptions about fairness between different athletes or across sports.

Williams has been a part of this complex and evolving anti-doping process since turning professional back in 1995. Earlier this year, however, she became frustrated with what she regards as inequities in the system. Just before the French Open in May, Williams informed her Twitter followers:

At the time, Williams had recently returned to tennis after having a baby and suffering post-birth health complications. Her low ranking did not reflect a decline in ability – rather, she had been out of the game. In other words, Williams was hardly a typical low-ranked player.

Then, just before the start of Wimbledon in late June, an article in Deadspin revealed that Williams had been tested five times by the US Anti-Doping Agency (USADA) in 2018, which was more than twice that of other top American women players.

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Williams responded to the report at Wimbledon by saying that she didn’t know she had been tested “three times more — in some cases five times more — than everyone else”, but emphasised she was fine with this amount of testing as long as the system was being equitably applied. A spokesperson later released a statement that made clear she felt she was being unfairly singled out:

…there is absolutely no reason for this kind of invasive and targeted treatment.

Then came another USADA drug test in late July and a further tweet by Williams, this time suggesting discrimination:

A few minutes later she posted an addendum to that message:

Targeted, rather than random

A key instrument in the World Anti-Doping Agency’s monitoring arsenal is longitudinal data provided through the Athlete Biological Passport, which began in 2009. This provides an analytical framework to detect unexpected changes in blood or steroid profiles among athletes.

Not surprisingly, drug testing of individual athletes remains core to anti-doping efforts, but there is now a more targeted approach to monitoring, with much less emphasis on random collecting of urine or blood samples.

It is indeed difficult to comprehend how drug-testing is carried out in tennis these days and why testing certain athletes is prioritised over others.

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By definition, a decision to target someone for a drug test is discriminatory. The key question is whether it is reasonable and proportionate to do so. In other words, what are the criteria by which drug testers are more likely to seek a urine or blood sample from one athlete over another? And when is it legitimate to discriminate in this way?

In its 121-page “Testing and Investigations”guide (2017), WADA advises athletes that:

Target Testing is a priority because random Testing, or even weighted random Testing, does not ensure that all of the appropriate Athletes will be tested enough.

So, target testing is, in part, a strategy to allocate resources where they are most needed. Importantly, though, WADA insists that a focus on particular athletes is not intended to cast suspicion on anyone individually. These athletes just happen to be in a pool of competitors that WADA considers a priority to “target test” based on one or more criteria.

The WADA guide lists various factors that may influence target testing by national agencies like USADA. Several appear to apply to Williams: athletes at the highest level of a sport (23 Grand Slam singles titles), athletes recovering from injury (shoulder issue), athletes in the later stages of their career (36 years old), and athletes returning to active participation after retirement (in this case, an extended break related to maternity leave).

Evidence suggests that testing frequency is reasonable

These factors suggest that USADA was target testing Williams in accordance with WADA standards.

While Williams has been tested more in 2018 than other top female players, including her sister Venus Williams (twice), Madison Keys (twice), and Sloane Stephens (once), a look back at the testing numbers in previous years is useful.

If we focus specifically on the Williams sisters, they were barely tested by USADA from 2001 (when records were provided to the public) to 2012, but that was also true for the majority of US tennis players. From 2013 onward, USADA became much more active in drug testing tennis players: over the next five years, Serena was tested 31 times and Venus 34 times.

Drug testing is not only the preserve of USADA. According to drug-testing data from the International Tennis Federation, Williams was tested 1-3 times in-competition (IC) and 1-3 times out-of-competition (OOC) through the ITF’s anti-doping program last year. This modest volume reflects the fact that she played just two tournaments and then took time off to have a baby.

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The year 2016 provides a more reliable gauge: in that year, the ITF program tested Williams 4-6 times IC and 7+ times OOC, the same ratio as her sister. Among other highly ranked US players, Keys and CoCo Vandeweghe were tested 7+ times IC and 7+ times OOC, while Stephens was tested 4-6 times IC and 7+ times OOC.

The 2015 ITF testing numbers and 2014 numbers are much the same.

There is, in short, no evidence that Williams is being unfairly targeted by drug testers. Her perception that she is being discriminated against appears to stem from a lack of awareness about publicly available information on who has been tested by different anti-doping organisations.

This misunderstanding is unfortunate, because Williams has used her enormous public profile to clumsily question the integrity of those tasked with the role of monitoring “clean sport”.

Drug testing is hardly a panacea for doping in sports, but if athletes wish to question why they have been targeted for biological samples, social media is hardly conducive to generating expert responses.