The public would be less likely to report a crime if a private firm was in charge of their personal data, a survey suggested today.

The poll of more than 1,200 people in the West Midlands showed the extent of public unease over a proposed £1.5 billion police privatisation scheme, the Unite union said.

The West Midlands and Surrey forces delayed the process to bring private firms further into policing yesterday "to allow engagement with the market, public consultation and to allow both forces to contribute to a safe and secure Olympics".

But the West Midlands force insisted it remained "committed to exploring with the private sector the potential to transform policing and to improve services to the public".

The project, which would be the largest police privatisation scheme in the UK, is not aimed at outsourcing particular jobs or roles, but instead using firms' expertise, systems and technology to transform the way forces do things, from beat patrols to murder investigations, the forces have said.

But Surrey Chief Constable Lynne Owens said there was a need to pause for further consultation in the face of concern among officers and the public.

Today's survey showed three in five of more than 1,200 people questioned in the West Midlands would be less likely to report a crime if their personal information was being accessed by a third party.

The same proportion also said they were not comfortable with private firms handling 999 calls, crime detection or investigations.

Peter Allenson, Unite's national officer, said: "West Midlands and Surrey police forces have realised that the public do not want privatisation but they have not dropped the plans altogether.

"They are simply buying themselves breathing space but no length of time will convince people that profit and policing are a good fit."

He added: "This is a very dangerous move which our survey shows risks alienating the public from the police force that is meant to serve it."

Unite commissioned research firm Mass1 to carry out the survey. A total of 1,211 face-to-face surveys were completed in Birmingham, Coventry and Wolverhampton between April 21 and 27.