Remember, folks, this site is not about politics. I ran into a sentence in a political context, though, that is such an excellent example of why I recommend against pronouns, that I have to quote it.
“The president believes in making sure that information is accurate before pushing it out as fact, when it certainly and clearly is not.”
What does that second “it” refer to? I predict that people will choose the antecedent based on their politics. And well they might. The sentence is not a good one, semantically speaking. It is hard to tell what the sentence literally means.
The rule with pronouns is that they should refer to the closest noun. This rule is so easy to break that ambiguity often results, and that’s the case here, and ambiguity is not something you want in a contentious environment.
I think this is what the speaker intended to mean (edited to remove ambiguity):
“The president believes in making sure that information is accurate before pushing [the information] out as fact, [especially] when the [so-called] information certainly and clearly is not accurate [to start with].”
Here’s what the grammar says:
“The president believes in making sure that information is accurate before pushing [the information] out as fact, when the [claimed] fact certainly and clearly is not accurate.”
I think That’s what was meant. Hard to tell. The second version is self-contradictory. Don’t jump all over me if you think I got it wrong, but feel free to put your own translation in the comments.
The rule: avoid pronouns. Say exactly what you mean.