On 30 July 2014, the ATO issued draft amendments to Practice Statement PS LA 2011/27 for public consultation by 28 August 2014 - see PS LA 2011/27(draft).
The subject of the Practice Statement is "Matters the Commissioner considers when determining whether the ATO view of the law should only be applied prospectively".
The purpose of the Practice Statement is "to explain the procedures for ATO personnel to follow and the matters to take into account in determining whether the ATO should not take action to apply its view of the law in past years or periods".
The amendments follow comments by the Full Court of the Federal Court in Macquarie Bank Ltd v FCT  FCAFC 119. The amendments clarify the Commissioner's previous position - they do not represent a U-turn.
In particular, paras 21, 28 and 33 to 36 have been added to the Practice Statement and para 37 (previously para 31) has been amended.
Para 21 seeks to amplify the concept of the Commissioner's "efficient, effective, economical and ethical use of resources" as required by s 15 of the Public Governance, Performance and Accountability Act 2013.
Para 28 seeks to balance a pattern of ATO conduct in relation to a single taxpayer with the desirability of treating taxpayers in comparable situations consistently.
Para 33 emphasises that nothing in the Practice Statement "is to be read as purporting to bind anyone in law to act contrary to the provisions of any statute".
Para 37 now states that in considering whether to apply a new view of the law, "research should also include speaking with external advisors or industry representatives, and internal ATO experts, who might have particular knowledge of the history of the ATO's dealings with the relevant industry or taxpayer group."