Even if the cops had heard him, the doctors who treated him wouldn't know if the cops were lying.
The judge, who had the final say about extending his observation beyond three days couldn't have known if I, the other friend, the cops, the paramedics and the doctors were lying.
There is often more nuance to real-life situations than "I contend that I didn't say that. He can't prove that I did say it."
Namely, my friend needed help. It was obvious to everyone, except him.
It wasn't a lie.