Stop and Search powers:
Parliament has - rightly - given the Police "stop and search" powers. As with any police power they must be exercised responsibly and lawfully. Lawful exercise includes avoidance of unlawful discrimination - see Equality Act 2010 s.149.
The Police and Criminal Evidence Act 1984 Part 1 (Stop and Search) is an important general stop and search power. Code of Practice A is applicable. There are further powers granted to the Police by other legislation - see the details set out in Code A.
The use of Stop and Search powers has often been controversial. One article (The Independent 6th August 2015 - Stop and Search: Can transparency end this abuse of Police powers?) states that: "The excessive and discriminatory use of stop-and-search powers is among the sorriest episodes in the history of the police over the past 30 years."
Recently, the use of the various powers has been the subject of two critical reports from HM Inspector of Constabulary:
Stop and Search Powers: Are the Police using them effectively and fairly? July 2013 - this report, found that police use of stop and search powers was too often ineffective in tackling crime and procedurally incorrect, thereby threatening the legitimacy of the police.
Stop and Search Powers 2: Are the Police using them effectively and fairly? March 2015
For some of the interesting history of this subject see Parliament Standard Note SN/HA/3878 (23rd January 2014) Police stop and search powers and the references therein to Lord Scarman's report on the 1981 Brixton Riots (2981: Cmnd 8427) and the Stephen Lawrence Inquiry of 1999: Cmnd 4262.
May the power to stop and search be removed from a constable?
The Guardian 18th August reports that Northamptonshire Police has agreed to "strip officers’ right to stop and search suspects if they are deemed to have abused the controversial law-enforcement tactic." This appears to be a policy introduced by the force's Police and Crime Commissioner who is reported as saying: "officers would have their stop-and-search powers removed if they had conducted searches that were deemed inappropriate on three occasions." The Guardian article indicates that eight police officers have been banned from being able to use the power on the streets. Six of the officers have seen their powers reinstated after completing additional training, while two remain unable to conduct searches.
Police and Crime Commissioners were created by the Police Reform and Social Responsibility Act 2011. Commissioners are elected and replaced the former Police Authorities. The 2011 Act set out the "functions" of the Commissioners but retained "direction and control" of a force with the Chief Constable. Section 2(3) states - "A police force, and the civilian staff of a police force, are under the direction and control of the chief constable of the force."
A Police Constable is an officer under the Crown and is personally responsible to the law for the conduct of his duties. A Police Discipline system applies and this was the subject of a review that reported in 2014 and the Home Secretary promised a "shake up" of the system (The Guardian 18th November 2014). Officers who misuse Police powers could be liable under this discipline process.
Within any particular Police Force it is clearly open to the Chief Constable to deploy officers as he sees fit and, no doubt, this might include moving an officer to duties which would not involve stop and search but it does not seem that there is an actual legal power to "strip" a constable of any of his legal authority. To that extent, the article in The Guardian 18th August 2015 is surely misleading.
Update 19th August:
Northamptonshire Police and Crime Commissioner - Stop and Search - One Year On. In October 2014, the Force established a "Reasonable Grounds Panel" to examine records of each search and, if thought appropriate, to offer training to both officers and supervisors. Since October 2014, 105 advisory emails have been sent to searching officers, 76 to supervisors. 9 searching officers and 10 supervisors have been suspended from undertaking stop and search until a development plan has been completed.
College of Policing 2015 - Definition of a fair and effective stop and search encounter
Martin Partington Blog - Use of stop and search by the Police: recent developments
Equality and Human Rights Commission March 2010 - Stop and Think