Off the top of my head:
The above is most suited for "nonfiction" books and newspaper-type articles. I'm not very familiar with likely-biased research papers, except in the sense that most researchers express a bias towards thinking their research is important and valuable...
(Source: rank amateur.)
I want to look into the research literature on an issue that has unfortunately become extremely politicized and controversial. (It isn't gun ownership, but let's say for the sake of argument that it is.) If I do a search for, say, "effects of gun ownership on crime", it is quite predictable that I will find a bunch of studies that say gun ownership decreases crime and a bunch of studies that say gun ownership increases crime. Some of those studies may be legitimate efforts at truthseeking, while others may be cherrypicked or manipulated, studies where the authors' bottom line has already been written before they do any work (to one degree or another), etc.
This seems like a potentially difficult environment to evaluate things in compared to one with less of a charged atmosphere, and I'm curious how best to navigate it -- any recommendations for how to best do that?