I saw that episode. It's not the sort of television I usually watch (I'm mainly into non-fiction tv), and so I don't remember the lead character's name. But I do remember him questioning the husband of the murder victim to the effect [paraphrase]...:
victim's husband: "Monogamy is just a social convention".
Mentalist (?): "Yeah, like not stealing or killing people".
This bit of dialogue was, for me, very off-putting!
If it was gay folk rather than poly folk at stake, that show'd be getting serious flak. Now it's okay to compare poly folk to murderers and thieves.
"The Mentalist" Code Red (2010)