OK, so maybe Columbo's first name was actually Frank

To update this post, where I said Lt. Columbo's name was Philip, I'd like to point you to the Wikipedia page for Columbo, that shows a screen cap from the episode "Dead Weight." It's a pic of Columbo's badge, and the pic clearly shows that his name is "Frank Columbo." The Wikipedia page says that the name "Philip" didn't start with the Kate Columbo series, but in a trivia book (which I used to own) by Fred L. Worth. He made up the name, hoping to catch people stealing trivia from his book (he sued Trivial Pursuit for $300 million, but the judge sided with Trivial Pursuit's defense that it was "research").

Of course, this doesn't put the whole story to rest. Even though it says "Frank Columbo" on his badge in the pic from the episode, it could have been just a name they came up with to fill in the first name spot on the badge, not thinking that anyone would actually catch it and hold them to it (this was before VCRs and DVDs, of course).

So, is it Philip or Frank? Until someone from the show says something 100% definite, we have to go with the evidence we have. Just like Columbo would. And in my opinion, the facts lean toward Frank.

Check out this Columbo site for the full background story.

[thanks to Bill for the info]