Yes, he actually has a long section on that. I didn't summarize it because I work in a setting where it's not usually an issue. You automatically take the client at their word unless there's some reason not to, and in my case, the "reason not to" tends to be super-obvious, like the court mandated client in total denial of an alcohol problem when they were referred for their fifth DUI or the obviously dysfunctional parents blaming everything on their completely normal, albeit stressed, kid.

Morrison worked in some settings where clients were sometimes faking/denying/exaggerating their problems for various reasons, so he gets much more into that. Red flags include outside evidence contradicted by client (like the DUIs), claiming symptoms that pretty much nobody ever has (our standard trauma inventory has "red flag questions" that very few people in any situation endorse, such as "Sometimes the left side of my body becomes paralyzed for several hours" and "I have a hard time controlling the urge to set fire to public buildings,") claiming symptoms that are extremely unusual for their stated disorder, inconsistent stories, etc. These point to lying, denial, or simply a wrong diagnosis - like, the inconsistent story person might actually have dementia.

With the TSI, if someone seems otherwise normal but endorses the paralysis question, you send them to a doctor immediately. If they seem otherwise normal but endorse the fire question, you evaluate for psychosis, pyromania, or just extreme anger. If they endorse BOTH, they are probably scamming you. (This is simplified. There are about ten questions like that on the test.) Endorsing a lot of weird, unrelated stuff that almost no on ever endorses at all suggests scamming, psychosis, dementia, or randomly answering without reading the questions. It's a red flag for "Investigate this."