The Spiral of Silence is an important political science and communications theory formulated by political scientist Elisabeth Noelle-Neumann that deals with decision-making in situations where the issue is controversial and may carry moral implications. It basically states that people holding views that are in the minority tend to keep them to themselves for fear of reprisal or rejection, and specifically social isolation. (Image via University of Twente) 
A recent study examined the individuals’ willingness to express their personal opinions in online versus offline settings and found that:
In the online community, where there are fewer physical constraints and concrete punishment concerns, every opinion has the possibility of being attacked and suppressed. Consequently individuals may select to remain silent. And as our findings suggest, individuals are not more likely to express opinions online versus offline settings and when people fear online isolation, they are less likely to express their opinions online. These findings combined showed no indication that the spiral of silence theory ceases to work in a virtual society. Rather, there are other variables, such as the fear of suppression and attack, which may smother individuals’ expressions in a virtual setting.
While recognizing the limitations of their study, the researchers also noted that:
Reinforced by expressing opinions online, individuals were more likely to speak out in other scenarios. This finding suggests that the Internet, as a democratic tool, not only can provide the public with a more efficient tool in monitoring the climate of opinion, but it may also directly serve as a mobilization factor in encouraging the public to participate in political deliberation….the Internet may serve as a catalyst to boost and exchange previously silenced opinions….Future studies could use an experimental method to test whether the Internet can improve an individual’s accuracy of assessing public opinion and to examine the degree to which opinion-climate monitored online could help fortify or disperse fear of isolation and speaking-out in public.
I am helping to run a blog about our local politics. We called it ‘Conversations’ and have tried to make it really easy for people to post and comment. We get very few people taking us up on it, as we first asked people to sign what they wrote. We are now allowing pen names and I am hoping that the discourse will pick up – and stay civil. We got a lot of anonymous snarky comments when we first tried this.
It’s sad – people seem to be afraid to say something serious in their own voices.
There is indeed a paradox here: We can now say anything in a cloak of anonymity, but likewise the crowd (or a small vocal part thereof) can silence us with attacks that are difficult to defend from. There is nothing wrong with majority-rule, but at least niche positions should get a fair, civil hearing. I like the way commentous.com is trying to address this…