Couple of people asked where the OP is from... I am from the UK, as is my friend, however the course is with a multi-national education institution, so views from all the world are valid.
Someone suggested listing country as a factor. - It was considered, as was religions, and other factors - however in order to make any meaningful comparisons a LOT of responses would be required from each country. Perhaps as a follow up different analysis could be done between selected countries.
To all the people saying, why not give anonymity - Take a look at the Jimmy Saville case - A number of people reported incidents to the police many years ago, but they were largely dismissed. IF these cases were publicised it's likely that other victims would have come forward at the time, and the prosecution taken more seriously. - I don't offer this as cause in it's own right, but as an example to consider the other side of the argument.
Personally - I think there is stigma for theft / murder - I'm not so sure if the stigma (or public mistrust) hangs around as long for those crimes. At the end of the day it's not my survey or thesis though. Perhaps a narrower scope generates more focussed responses. If you broadened it to all crimes a) you might undermine confidence in the judicial system, and b) the responses might be along the lines of "Yes for this crime, no for that crime"
Thanks to all those that have completed the survey so far, it's helped boost the numbers a bit... more responses are still needed however, so if you're interested in this topic, and not yet completed the survey, the link is on the first page.
Thanks