Speaking at Spiked's 'Enemies of the state: Religious freedom and the new repression' event in London on Wednesday, Ginsberg said it was "vital" for everyone to be able to express their conscience even when some views "challenge the status quo".
"Those critical of gay marriage - because as Christians they believed it to be wrong - felt their views were shut down. They weren't allowed even to express their own personal beliefs and conscience...the failure to be willing to listen to those with whom we disagree has led to the development of intolerance," she said.
She argued that silencing people with unpopular views would result in blasphemy laws being reintroduced "by the back door".
"Blasphemy Law in the UK was only abolished in 2008, but I would argue its creeping back into liberal democracies in other ways that mean in effect we're reintroducing the notion of blasphemy by the back door.
"It means for example that criticism of radical Islam is considered to be islamophobic and that criticism is shut down, meaning we close off any debate about whether we think radical Islam is a good or bad thing.
"If we start to shut those people down from expressing their opinions and their conscience, we can't have a debate about the underlying rights and wrongs about the issues."
Speaking as part of a panel discussion on 'The conscience question: Are we free people?' Ginsberg argued that freedom of conscience should apply both privately and publicly.
"We need to defend freedom of conscience not just as our right to think privately in the privacy of our own homes, but the vital need for us to be able to voice that inner voice externally so we can debate, discuss and come to some kind of consensus about the kind of world we want to live in together."
The event was sponsored by ADF International - an organisation aiming to better educate the Christian community on the legal issues that affect its ability to live out their faith.
