The question has been posed “Could security staff spray a dye onto people committing offences to enable them and by extension the police, to identify them later?”
To answer this one needs to define a number of aspects of the question.
To begin with I will assume that the incident will happen in England and Wales. I define police as someone who holds a warrant as a police constable and security staff as anyone who is employed and is working on private property, for example as door staff.
So in answer to the question, anyone could spray a dye onto anyone else if they had the product to hand and yes this would potentially assist in the later identification of offenders or witnesses to the incident where the dye had been deployed.
But would this be lawful? Neither the police and Criminal Evidence Act 1984 nor common law have anything to say on the matter.
However for police officers there is a requirement to act proportionately, lawfully, appropriately and their action(s) must be necessary [PLAN]. There is no current legislation that covers spraying dye on offenders nor is it a tactic available to public order commanders.
For security staff again there is no legislation covering the use of dye. I argue though that they should follow the police legal requirement to ‘PLAN’. Under this and considering that the suspect(s) are on private property the following protections may apply.
If the organisers or operators specifically warn attendees that it is part of the terms and conditions of their attendance that a dye could be deployed to identify persons involved in disorder or a criminal offence.
It could be argued that this could tend to mitigate the chance of people offending or observing an offence for fear of being ‘dyed’.
However the actions of the security personnel would need to be recorded by CCTV, body cam or another official to support the PLAN decision making and the dyes use.
This would not however prevent the user of the dye from being considered for causing criminal damage or being sued under civil law for damages.
Furthermore under current Health and Safety legislation an employee and their employer have a safety responsibility towards anyone on their property which is subject to the lesser Civil Law burden of proof. How this sits with a complaint about being dyed would need to be determined.
The point is that there is no legal precedent for the use of dye to help identify suspects in a crowd whereas there is in the protection of cash in transit. The use of dye in the proposed way would have to be tested in the courts. I am certain this would lead to years of litigation and challenge all the way to the supreme court so anyone wishing to try dyeing suspects should expect to be challenged. Moreover they should check with their insurers that they will be supported. Finally they must ensure that the colorant is not deployed in a public place as this may place the user in conflict with the police. I would also be concerned for their SIA license as the authority are quick to suspend members pending the resolution of legal action.