I'm sitting in the gate area at HNL. The TSA agent scrutinized my brand new driver's license with a black light as if it was a controversial museum artifact. He looked particularly stupid. It's just one more way they manage to make fools of themselves.

same thing happened to me last wednesday. the guy looked foolish studying my license for what seemed like forever with a line behind us.

What are they looking for? Some left over biological residue? Maybe they should use those blacklights to scan the floors that we walk shoeless on at the checkpoint? @:-)

Those blacklights are often to find the watermark that is only seen in UV light. Thats exactly what they were looking for on your drivers license ID.

Sanosuke!

He checked your ID in the gate area, or when you were lining up? How long did the ID check take? Did he ask any other questions?

As stated by Sanosuke they were looking for the watermark. It's used on the driver's license and passport to check for forgery; it's also on credit cards too.

I didn't know watermarks could be embedded into plastic.

There was a certain CWL do where a bunch of FTers could be found examining their credit cards cos one of us (ok me!) had heard this and there was a UV light in the club so we wanted to test it

It's true... all the ones we checked have a logo which fluoresces under UV.

Yes, I know there's a UV-visible watermark. But can someone explain how this keeps me an other travellers safe?

Simple: we all know that The Terrorists always travel with forged IDs, right?

Or, maybe it's a new program to catch illegals in the USA?

Or a make-work project for UV lamp manufacturers?

Seems silly. You can buy the watermarked plastic cards at a legit supplier, or you can get them on eBay. Forge away!

It's on the skin on the outside of the card.

Mastercard has a big MC, visa has a bird, Amex i think has a AX I can't remember and I have no idea what Discover has.

If you are ever in any kind of night club with black lights you can notice it.

My DL was issued in 1988, and I re-laminate it myself at Office Depot every time I get a renewal sticker - I doubt it has a watermark.

It expires in 2012, so I'm not getting a new one just because the TSA's little toy can't detect something that isn't there.

Not every state has holograms on their drivers licenses. They've been doing this for a while at some airports (DTW)

Well, it should be obvious. If your home printed BP name doesn't match the name on your blacklight checked ID, then you're a terrorist. E-duh.

Why would we think any of this should be logical or defensible? It's no different than the 3, or 3.4 fl. oz. rule (except for flight crew members), the sno-globe rule, the shoes off (except for flight crew members) rules the everyone must be screened rule (except for flight crew members). The exceptions alone are tremendously illuminating. The basis for all this crap is the TSA pre-guessing that the gullible among the travelling public will presume that if they are inconvenienced or annoyed by security, security must actually be quite effective.
I think PT Barnum had a theorem that supports this, BTW.
Hence the frequent circus references on this and many other areas where most posters actually posses a modicum of intelligence.