why do journalists and authors often put brackets around words in seemingly strange parts of sentences?

Question

For example, a sentence I just read went as follows:

> “‘I don’t think [the book] had anything to do with his arrest and neither does Anne Marie Schubert,’ he says.”—(Excerpt from the appendix of ‘I’ll Be Gone in the Dark’ by Michelle McNamara)

Found in Other.

Answer 1

They’re changing part of a quote from something understood in context of the quote to something explicit. In your quote [the book] was probably “it” or similar.