Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013
These regulations were required to be made by the European Union's Directive 2011/83/EU. They specify the circumstances in which consumers can cancel contracts and the related information which must be supplied by traders. Legal Aid is not specifically excluded, but the regulations (in relation to the "Information requirements" Part 2 and the "Right to cancel" Part 3) state that "This Part does not apply to off-premises contracts under which the payment to be made by the consumer is not more than £42" (regulations 3(4) and 27(3)). In force 13/6/14.
External links
If the link above does not work (sometimes a problem with the Legislaton.gov.uk website) then try this or this
Law Society, 'Consumer Contracts Regulations 2013' (Practice Note, 15/5/14)