Not P but DFW: refer the call

[Mike Jing]

The following excerpt is from David Foster Wallace's *Host*:

Q: If a drunk driver calls in, do you have to notify the police or
something?
A: “Well, this is why screening is tricky. You’ll get, say, somebody
calling in saying they’re going to commit suicide — sometimes you have to
refer the call. But sometimes you’re getting pranked.

What does "refer the call" mean exactly?