The Conservative Party would cut or kill new and proposed IT projects worth at least £8bn, with the national identity card and the Interception Modernisation Programme (IMP) top of the list.
In a paper on the effective use of IT in government for the Centre for Policy Studies, Liam Maxwell, said the government spent £16.5bn a year - about 1.4% of GDP - on IT, but only 30% of projects succeeded.
He said the way forward was to scrap government's penchant for large, centralised databases and to "yield control of personal data to individual citizens".
He said the potential benefits included estimated savings of 50% on IT spending, more flexibility, better public services, greater security and more privacy over data, and far less intrusion of the state into people's lives.
"It would reverse the government's attempt to nationalise (personal) data by giving back control to those who own it: us," he said.
Maxwell said reform would not be easy. IT projects had "institutional momentum", he said. He said the National Programme for IT, the NHS's troubled new £12bn IT project, could have been given to the private sector, such as Google Health or Microsoft's HealthVault.
It would be easier to scrap large early stage programmes like the £5bn ID card scheme and the £12bn IMP, where there was "some political will" to abandon them, as shown by shadow chancellor George Osborne's earlier promises, he said.
Maxwell quoted a study by the London School of Economics which found that out of 142 million contacts with the public at the Department for Work and Pensions, only 340,000 (0.025%) were online.
He said government was meant to cut its running cost by increasing online usage. "It has at times been staggeringly unsuccessful," he said.
Maxwell said government plans relied on the state having a "panopticon" view into every aspect of people's lives. He said this view meant that government had neither understood nor reacted to social networking factors such as "localism, user input and collaboration".
He said many people were happy to share even intimate details of their lives on web sites like Facebook and Linked-in. "But they like to control their own data and who can see it."