Data-sharing would also allow council tax inspectors to "raid" other databases such as the Land Registry to build up detailed records of every home, including taxable features such as scenic views and gardens.
"There is already public concern at government plans for a compulsory Identity Card Database, a nanny-state Children's Database and a property database for the council tax revaluation."
"Step by step, the government is logging details of every man, woman and child - and their home - in 'Big Brother' computers.
"For all of Labour's talk of human rights, it's clear their state inspectors have little respect for people's privacy."
Campaign organisation NO2ID - which has vehemently opposed the introduction of compulsory ID cards - criticised the government's "intention to reverse the presumptions of confidentiality".
"From now on, you can assume that anything you tell to an official or public servant will not only go on your record, but be passed on to anyone at all in 'the public interest'," said its national coordinator, Phil Booth.
"How many thousands of officials will now have free rein to snoop on your personal, business and children's lives?"