Earlier this year I posted a series of articles explaining what scientific peer-review is, and what it isn't. The series was very popular so I've decided to create this single post that links to all the previous ones.
In Part 1 we gave a basic definition of peer-review, described the process, what it is expected to accomplish, and what it is not expected to accomplish. In a nutshell, scientists conduct research and then write that research up in a formal paper (including methods, results, how the statistics were done, conclusions, and some discussion of what it all means). The paper is then submitted to a scientific journal, whose editors send it out to other scientists in the field who are capable of reviewing it for clarity, content, and value to expanding our collective knowledge. The reviewers don't validate or invalidate the work, just make sure it meets some basic scientific principles and complete enough for others to 1) know what the researchers did, and 2) replicate it.
Part 2 looked at how peer-review can go wrong. Standards for scientific journals can differ, with some being akin to Ivy League colleges while others may be less stringent. The relatively rare problem of "pal-review" (common among climate deniers) was examined, as was the difficulties caused by some (but not all) of the new "open access journals."
Part 3 looked at some people who have intentionally abused the peer-review system. In addition to the other points point in the article, it also highlights a prime example of intentional abuse - the pal-review case in which Willie Soon and Sally Baliunas were paid to write an error-filled "review paper" (i.e., no new research) that was spearheaded through a suspect review process at a policy journal notorious for printing faulty (see "error-filled") papers by climate deniers funded by industry lobbyists.
The final article, Part 4, examined how the internet (which is not peer-reviewed) has been used by climate denier lobbyists to bypass the peer-review system. One tactic used is posting something on a blog that would not withstand the scientific scrutiny of peer-review, then citing it as if it were valid science. Another tactic is to take any paper that did get through peer-review (which, as Part 1 noted, is only the first, most basic review) and then promote that single paper as if it overturns 100+ years of unequivocal science and the more than 100,000 other peer-reviewed papers that demonstrate the single one to be wrong. As already noted, most denier papers don't stand up to even minor scrutiny.
The sum of these four articles, along with many other articles here on The Dake Page, provide a good background on how scientific peer-review works, what are its limitations, and how some lobbyists have tried to abuse or bypass completely the process. Be sure to follow the links in each article to sources and further information as these help flesh out the points made.