Stephen Relf assesses reaction to the Aaranson report into the possible introduction of a UK GAAR In December 2010, the government set up a study group led by Graham Aaronson QC to consider if the UK would benefit from the introduction of a general anti-avoidance rule (GAAR). The conclusion reached by the study group, as set out in a report published by Graham Aaronson QC in November 2011 is that the introduction of a ‘moderate’ GAAR would be beneficial.