"Couples Who Kill" or "Couples That Kill"?

I favor “who” since it’s referring to people; I’m old-fashioned that way. If the killing couples are mountain lions, on the other hand, I’m okay with “that.”

As it’s referring to people, “who” seems right to me.

“Who.”

But in informal everyday speech, a lot of people would say “that,” and no one would think it odd.

Hrmmm, “who” 3, “that” 0.
Must be me then…...

And if we put something in front of those three words, like: “The following program is about couples that kill.” ?

Thanks, by the way, for your answers.

Maybe the word “couple” signifies a unit. Not two individual killers. A unit then becomes a single body. Not plural. “That” would work in this case.

I’m with @woodcutter. If “couples who kill”, then it refers to the two people in the couple, killing people. If “couples that kill”, then it refers to the unit of the couple, killing people. I am actually picturing them picking up a weapon together, each person with a hand on the gun or knife.

No one would ever use the latter, so I am inclined to say it should be “couples who kill”. But since this is based entirely on my gut feeling on the matter and nothing else, who knows? :D

Human couples…“who.” Bonnie and Clyde are an example of couples who kill.

Animal couples…“that.” Scar and Zira (in The Lion King) are examples of couples that kill.

I like “that”, but I’m old fashioned that way. “That” has been used with human antecedents for at least 500 years. “Our father that art in heaven”, etc.

I would prefer Killing Couples possibly Couples Killing.

Both the previous statements sounded clunky, personally.

Killing Couples sounds like there is a serial killer going around killing couples. How about Killer Couples instead?

AS for the original question—Couples Who Kill. And I think sentient talking lions are who as well. Couples that kill could be .. Pop Rocks and Pepsi.

A group that is doing a common thing, like a military unit. It will be made up of individual soldiers but they all have the same patch on their shoulders. The unit would be called a
“that” The unit “that” killed Bin-laden. Sounds more appropriate to me anyway.

I have found the right porn for all of you.

Well, the lead up anyway. SFW.

The unit “responsible for” killing Bin Laden

@keobooks.. Just right

More killing couples: cigarettes and alcohol.

Couples Who Kill sounds better. Couples That Kill is grammatically acceptable. Couples Whom Kill, definitely no.

“Responsible” sort of smacks of wrong doing in the context of killing. Thats why my example of someone worthy of worm dirt was used. Or..fish food.