Firstly, a criminal identifier spray differs considerably from that of pepper spray.
Many people simply assume they are the same thing: nothing could be further from the truth..!

The essence behind a pepper spray is actually to cause harm to a person by inflicting enough pain to incapacitate them.
For instance, it will give them blurred vision and burning eye pain!

More importantly, pepper spray contains a noxious gas which is designed to cause harm.
For the general public, this makes pepper spray totally illegal to buy, own and use in the UK. 

Source link: https://www.ukpreppersguide.co.uk/legal-criminal-identifier-spray-uk/ by UK Prepper at www.ukpreppersguide.co.uk