Information on numbers of investigations is not held centrally by the Security Industry Authority (SIA) and could be provided only at disproportionate cost.
The SIA does however have figures for the total number of outcomes of its investigations, since the relevant offences under the Private Security Industry Act 2001 were designated from June 2004 onwards:
Number issued Written warnings issued 1,092 Improvement notices issued 87 Licence revocations 12,632