In an effort to tackle the exceptionally high level of alcohol consumption in the Northern Territory (NT) of Australia, there are a suite of alcohol policies and new legislation that have been introduced. These include restricted purchasing and consumption for certain individuals. In 2017, the Banned Drinker Register (BDR) was (re)introduced – a policy that involves placing persons who consume alcohol at harmful levels to themselves or others onto a register which prohibits the purchase of alcohol from take‐away liquor outlets. As a result, there is an incentive for banned drinkers to obtain alcohol through friends, family, and through the black market – referred to as secondary supply. Though the phenomenon of secondary supply is not new, the recent evaluation of the BDR highlighted a number of challenges of tackling the secondary supply of alcohol. Informed by Head's framework for assessing ‘wicked’ policy problems, this policy analysis uses data from interviews with stakeholders undertaken as part of two studies on alcohol policy and services. The findings present the limitations of the policy design and implementation context in preventing secondary supply of alcohol to banned drinkers. The paper concludes with implications for policy and research that better recognise the implementation context.