Here is a summary of why dual members are unable to serve past the group level.
Dual Member History – This gives a history of the policy about dual member service and a page of frequently asked questions. It shows the policy has been in place from the beginning, was recommended by Bill W, and has been reviewed many times over the years by the World Service Conference and the Policy Committee of the WSO. Each time they have reaffirmed the policy.
Dual Members in Service Policy This is a memorandum from the WSO to answer questions including whether excluding alcoholics from service is a discriminatory policy.
Letter–9-15-1971–Additional Dual Member Background Information view and
Letter–10-16-1968–Additional Dual Member Background Information.pdf view
These are copies of old letters sent as replies to members about the questions about dual membership service.
The Al-Anon/Alateen Service Manual (pages 86-87 in 2018-2021 Version 2 edition) says:
Al‑Anon Family Groups and Alcoholics Anonymous (A.A.) share a common spiritual legacy in A.A.’s Twelve Steps and Twelve Traditions. Before Al‑Anon was founded, family groups met with and beside A.A. groups. In 1951, various family groups banded together and agreed to organize Al‑Anon Family Groups, a program dedicated to helping the friends and families of alcoholics. Over the years, Al‑Anon developed its own service structure, based on the model provided by A.A.’s experience and guided by the Twelve Traditions.
Tradition Five defines Al‑Anon’s single purpose. Tradition Six encourages cooperation with Alcoholics Anonymous, maintaining that Al‑Anon is a separate entity that ought never affiliate or the appearance of affiliation with any outside enterprise. Putting these principles into practice maintains a separation between the service structures of Al‑Anon and A.A. This separation helps avoid the appearance of a conflict of interest and safeguards Al‑Anon’s singleness of purpose. Accordingly, Al‑Anon’s policy is that members who are also members of A.A. do not serve as Group Representative (GR), District Representative (DR), Area Delegate, World Service Conference member, alternate to any of these service positions or on any committee of the World Service Office.
Filling service positions is a matter of District and Area autonomy, within this policy and the spiritual principles that form its basis. Tradition Four grants autonomy to local service arms, except in matters affecting Al‑Anon or A.A. as a whole. Al‑Anon members who are also members of A.A. participate fully in all group activities, including group conscience decisions. However, they do not hold Al‑Anon service positions that vote in matters affecting another group or Al‑Anon or A.A. as a whole.