The High Court has been assiduous in ensuring that, if the validity of a search warrant is challenged, all statutory formalities have been complied with. Formalities may relate to the actual issuing of the warrant or to its subsequent execution. This is well illustrated by the case of Redknapp v City of London Police and City of London Magistrates Court  EWHC 1177 (Admin) where a warrant, issued by a JP, was held to be unlawful for non-compliance with the Police and Criminal Evidence Act 1984 s8(3). It is also clear from this judgment [para 13] that adequate notes should be kept by the court as to the material put forward by the Police in support of their application for a warrant. The warrant issued to search Mr Redknapp's home was executed and the press were present. Although the High Court did not find that the press had been "tipped off" such an inference does not seem unreasonable. The Redknapp case is discussed at some length by Neil Parpworth in Criminal Law and Justice Weekly - 13th December 2008.
The Berkshire home of Sir Cliff Richard
has been recently searched by the Police acting under a warrant issued by the Magistrates court. The search took place when Sir Cliff was absent abroad and it took place in a blaze of publicity. Geoffrey Robertson QC is highly critical of this - see his article published by The Independent on 16th August 2014. Robertson sees the way in which Sir Cliff Richard has been treated as completely unacceptable. Whether it was actually unlawful may yet be tested before the High Court.
A major concern is the attendant extensive publicity and South Yorkshire Police have admitted working with the media before searching the property. As Robertson notes -
The involvement of the media in this way may yet raise important issues relating to due process and fair trial (Article 6 of the European Convention on Human Rights).
Without knowing the full circumstances surrounding the issuing of the warrant, I hesitate to agree with Robertson that all search warrants should be issued by judges though, in fairness, the idea will not be without attraction to some. In daily practice, "lay justices" - properly advised as to the relevant law - deal, in most cases, with these applications. However, out of court hours, it is not unknown for the police to visit the home of a lay justice to ask for a warrant. Perhaps, at the very least, a legally qualified legal adviser ought to be always present. Magistrates' Courts have procedures in place for handling these applications. In 2013, the Justices Clerks Society issued guidance - (HERE). The Magistrates' Blog has the following posts on search warrants
Search warrants (1) ........ Search warrants (2) ......... Search warrants (3)
and also see UK Police Law Blog
PACE Code B -
Justices Clerks Society - Search warrants