CAS will have a field day on any of this, but thanks for coming.
I gave some consideration to this, and here are my thoughts. Article 10 of the WADA code per se does not prohibit an international sports federation like the ITF from sanctioning ADRV offenders beyond what the WADA code specifies. The commentary at the end of article refers to harmonization of penalties across sports, but recognizes that harmonization "has been one of the most discussed and debated areas of antidoping". Article 10.10 specifically allows international federations to impose additional financial sanctions using their own additional rules, provided that the maximum period of ineligibility has been given. However, article 23.2.2 of the WADA code may have a bearing on a penalty that alters the ban time, since it requires that
No additional provision may be added to a Signatory’s rules which changes the effect of the Articles enumerated in this Article [a list that includes article 10 which outlines the ban times].
So the legal question on whether ITF can prohibit wildcards for a period after returning from a doping ban depends on whether this is (a) an extension of the ban time, (b) an additional penalty for ADRV offenders, or (c) something that simply enforces ethics and priorities of the organization. Interpretation (a) will be probably disallowed by CAS; (b) might or might not; and (c) is safe.
I think that interpretation (a) is clearly incorrect and will not be accepted by CAS. Refusing such an athlete a wildcard clearly does not extend the ban time, since the athlete can still participate in events that their ranking allows just as any other athlete returning from a long absence or a freshly starting athlete. Adopting interpretation (a) and disallowing this under the WADA code leads to absurdities like giving the legal right to protected ranking to ADRV offenders too.
Whether the board member's proposal is (b) or (c) is I believe a matter of interpretation. Certainly an organization has the right to impose additional requirements for participation in events it organizes; for example, no one has successfully went to CAS because they want to play on the WTA circuit at age 12. In my opinion, a prohibition of wild cards for a limited time after a doping ban can be justified as serving three purposes, all within the spirit of (c):
1. ITF wants to promote clean sport, and does not like it when ADRV offenders do not suffer the full consequences of their ban, so they prohibit the practice.
2. Making wildcards available to such offenders generates negative publicity for the sport, therefore ITF acts to protect the sport's interests.
3. Wildcards are a privilege, not a right for anybody, therefore ITF is entitled to set its own rules for them.
It is interesting here to examine prior related CAS rulings. There are no such rulings about wildcards, but the story of the "Osaka rule" in the Olympics is instructive. At their meeting in Osaka in 2007, the International Olympic Committee's Executive Board enacted the following rule:
Any person who has been sanctioned with a suspension of more than six months by any anti-doping organization for any violation of any anti-doping regulations may not participate, in any capacity, in the next edition of the Games of the Olympiad and of the Olympic Winter Games following the date of expiry of such suspension.
Now this rule is much stronger than the proposed prohibition of wildcards. It actually extends the ban of affected athletes from the Olympics for up to four years beyond what the WADA code specifies. There is no alternative means of entering, unlike with wildcards.
The IOC sought and obtained a concurring advisory opinion from CAS that the "Osaka rule" was consistent with the WADA code. The arbitrators on the panel found that the intent of the Osaka rule was not to extend the ban, but to clarify eligibility criteria for athletes.
However, a later CAS panel reversed the judgment on the grounds that the rule prevented the athlete's entry by any means, and therefore had the effect of extending the period of ineligibility beyond the WADA code proscriptions and generated "double jeopardy" conditions for the athletes. Even then, with CAS divided, they noted that
“If the IOC issued a rule that persons convicted of a violent felony were not eligible to participate in the Olympic Games, such a rule would likely not violate the principle of ne bis in idem, because the effective purpose of that sanction would be different from the purpose of the criminal penalty associated with that violent felony.”
I conclude from the above that as long as the ITF bases the prohibition of wildcards on ethical criteria about what is best for the sport and its image, and not as a sanction for ADRV offenders, the new rule should be safe from challenge in CAS.