Privacy International has slammed the Information Commissioner's Office (ICO) ruling that Google Street View does not contravene the Data Protection Act.
The privacy watchdog said the ICO is not fit for purpose. It has demanded a "root and branch" overhaul by Parliament.
The ICO responded to a complaint by Privacy International by saying the removal of the Google service would be "disproportionate" to the relatively small risk to privacy.
"There is no law against anyone taking pictures of people in the street," an ICO spokesman said.
The ICO has re-iterated that it is satisfied that Google is putting in place adequate safeguards to minimise any risk to the privacy and safety of individuals.
The ICO will be watching closely to ensure Google continues to respond quickly to deletion requests and complaints, a spokesman said.
Privacy International said the ICO's response proved that the regulator has abandoned principled protections in favour of commercial and technological popularity.
"We believe the commissioner's stance is far too pragmatic and lacks the rigor that is necessary to protect Britain from the encroachment of the surveillance society," said Simon Davies, director of Privacy International.
"We challenge the incoming commissioner to find the courage to defend the legal principle of privacy and thus restore public trust in his office," he said.
Christopher Graham, director general of the Advertising Standards Authority, is expected to become the next UK Information Commissioner after Richard Thomas retires on 30 June.