PETA

[xoxoxoBruce]

Sentience, n.
The quality or state of being sentient; consciousness.
Feeling as distinguished from perception or thought.

Sentient, adj.
Having sense perception; conscious: "The living knew themselves just sentient puppets on God's stage" (T.E. Lawrence).
Experiencing sensation or feeling.

Uh,...Do you mean a critter would have to know they were killing another critter, Dana? As opposed to kicking it's ass until it happened to die? I'm confused.
I think animals understand when another animal is dead vs alive, but they'll never attach all the ramifications people do, to death. I'm convinced that when a lion grabs a victims throat, they're aware the victim is going to end up in a state of what the lion understands to be dead. It's intentional and premeditated, which only leaves "justified" as the determining factor between killing and murder.
Maybe.