Explain how they benefit.
How the liars benefit? In the two big Southern cases, the MEs were not only working for their state/city departments but also contracting work. They had so many cases, they just made stuff up to get through them. In some cases, they had high profiles and big egos. They were known to "nail" people, go into court and testify for the prosecution. Notoriety. So that one another motive. Little of it was personal. Some people are nut jobs. Just like that Fire Chief who was actually the one starting the fires....then showing up at the scenes. The case where this guy went to jail for torching his business for the insurance...only to find out later there was no arson, after he'd spent time in jail..I think some of these people have a "hunch" that someone is guilty and just help things along because their (the dirty ones) egos are huge, they overestimate the accuracy of their intuition. Every profession has its bad eggs.