I think there are several levels to this question:

1. Any issue based on Politics or Religion will have experts on both sides arguing for their case based on their own personal choice and biases - these are more often than not, arguments and discussions rooted entirely on opinion.

2. For controversial issues in Science and Economics I will try to determine if there are any biases based on point 1. In some cases this becomes visible based on the political leanings of the Scientists and / or corporate sponsorship of the study.

3. In the Maths world there doesn't seem to be any controversial issues over the results (which is why I kind of like maths a lot!), however there are many issues on which approach to take and how useful a result is. For those sorts of predictive issues I don't usually have a strong opinion

So in general, it comes down to what the biases are. Everyone has an opinion, and these are (or ought to be) less relevant the deeper you get into the Science and Maths.