Purdah is a classic of British political convention…unwritten…of uncertain status and often imprecise .’. a self-denying ordinance applied on a case-to-case basis…not enshrined in law.
It is in reality just custom and practice…with a healthy dose of common sense! It needs to be understood by reference to the way public bodies behave in practice rather than the application of rigid rules.
It is the period between the notice of the election (for 2017…to be published on 27 March 2017) and the date of the election itself (4 May 2017). Purdah is a term commonly used to mean the period in the run-up to an election when the normal protocols and behaviours around a council’s (or a member’s or officer’s) activities in general and around publicity and communications in particular, become more restricted.
Full guidance for members and officers in the period leading up to an election can be found at Who gives a purdah!