UK CCTV camera numbers are thought to be among the world's highest
British people have been "careless" with their civil liberties, but that is beginning to change, former shadow home affairs minister David Davis has said.
Speaking at the Convention on Modern Liberty on Saturday, Mr Davis said people were growing increasingly angry at government intrusion in their lives.
More than 1,000 people joined the event in London and at venues across the UK.
Other speakers included former Guantanamo Bay detainee Moazzam Begg and Liberty director Shami Chakrabarti.
Gatherings were also be held in Belfast, Bristol, Cambridge, Cardiff, Glasgow and Manchester to debate issues such as the "database state", counter-terrorism laws and press freedom.
Mr Davis, who resigned from the Conservative front bench last year to fight a by-election on the issue of civil liberties, said the British public had been "casual" with their freedom and privacy in the past.
"They treat it carelessly, like a very old suit that they have had a very long time, [but] times are changing.
"Something is happening in the hearts and minds of our country."
Mr Davis said policies like ID cards and detention without trial for terror suspects were initially popular with the electorate, but were now drawing widespread opposition.
Others speaking at the convention agreed with him. Human rights lawyer and life peer Helena Kennedy QC, said communities were "being alienated" by the increased use of anti-terror laws beyond their original remit.
"There is a general feeling that in creating a climate of fear people have been writing a blank cheque to government," she said.
"People feel the fear of terrorism is being used to take away a lot of rights."
She added that people were "fearful of the general business of collecting too much information about individuals".
Also speaking to the London event was Mr Begg. He was asked about fellow detainee Binyam Mohamed, who was released from Guantanamo and returned to Britain this week.
Mr Mohamed claims he was tortured while in US custody - and with UK knowledge - and Mr Begg said he was "eager to pursue justice" for his alleged treatment.
"He does not want to talk about the torture, which I understand because it was much worse for him than it was for the rest of us," he said.
"But there is clearly a feeling in his mind that he has a duty to speak out for those that remain behind but also to expose the secret detention process."
Mr Begg said it was "time to look right in our back yard" at Britain's role in the alleged mistreatment of terror suspects.
Shadow justice secretary Dominic Grieve also spoke to the London audience, arguing that the government's desire to control risk in society was "destroying our quality of life".
"We have to accept that society and life carries risk and whilst it is the duty of the state to do its best to moderate and prevent what is wrong, nevertheless there are finite limits," he said.
"We, as citizens, have to make this clear to government, we are prepared consciously as adults to accept some element of risk in order to be free."
The government's plans to extend the period terrorist suspects can be held before being charged led to a large Labour rebellion last year - and prompted Mr Davis's resignation.
They were later shelved following a heavy defeat in the House of Lords.
Last week the Liberal Democrats unveiled their "Freedom Bill" and pledged a review of the use of CCTV cameras, the abolition of ID cards and control orders for terrorism suspects.
And earlier this month the Lords constitution committee warned that electronic surveillance and collection of personal data were "pervasive" in British society and threatened to undermine democracy.
Last year Gordon Brown defended the use of CCTV, ID cards and the DNA database in a speech on civil liberties - saying they helped ensure people's right to live free from crime.