Why is this called Cat O' Nine Tails?

At almost 50 minutes into the movie, James Franciscus says there are 9 leads to follow and then comments, "It's a cat with nine tails."

Karl Malden then remarks, "A cat of nine tails, like the old naval whip."

It's really just referring to the multiple leads they (the reporter and blind man) need to follow to uncover the actual mystery/killer.