This page is an essay on Verifiability, Biography of a living person, Words to watch § Contentious labels, Offensive material, and Writing better articles § Principle of least astonishment.
What precisely is a "Contentious claim?"
The definition of that is one of the sources of many morasses in the realm of articles on Wikipedia, and especially the biographies of living persons.
Some are fairly clear:
- "John Doe is a racist axe-murderer" would generally conceded to be "contentious" and thus requiring strong reliable sourcing for the claim.
Some are less clear-cut:
- "John Doe was seen leering at his neighbor's cat." Is that just a "harmless bit" in a biography, or is it "contentious?"
Common English dictionaries use some variant of "controversial' or "likely to cause an argument".
The problem is that everyone has a different view of what "controversial" means, even as they clearly argue about the claim!
Dictionaries fall down here -- just saying "related to controversy" or some other recursive definition. So let's look at the "argument" side.
One way of looking at it is ... if another editor says it is "contentious" then it is. Frequently this leads to a Monty Pythonesque sketch about the "argument department" or the like, with the second editor insisting "of course it is not contentious."
Another is "we are having an argument, so the claim is ipso facto contentious." Which is a tad easier to reach.
Perhaps recognising that articles are the sum of their parts is a valid course of action. Editors should view the "contentious claim" quite aside from the person whom it is attached to, and ask frankly whether they would have a problem with that edit being about their favourite (or least favourite) person in the world.