You may have seen a couple of weeks ago that presidential candidate Chris Christie, governor of New Jersey, believes that logistics technology can play a role in dealing with immigrants in the US.

"You go online and at any moment, FedEx can tell you where that package is," he said at a recent campaign stop. "Yet we let people come into this country with visas, and the minute they come in, we lose track of them."

Christie added, "We need to have a system that tracks you from the moment you come in and then when your time is up. However long your visa is, then we go get you and tap you on the shoulder and say, 'Excuse me, it's time to go.'"

"I'm going to have Fred Smith, the founder of FedEx, come work for the government for three months," to show us how to do it, Christie said.

Shortly thereafter, I received a call from an editor at The Huffington Post who wanted to know my thoughts on whether such a thing is possible. We talked for a long time, and of course the short answer is No, as came through in the piece he wrote based on the interview with me, which you will find here: Tracking Immigrants Like FedEx Packages Doesn't Actually Make A Lot Of Sense

We actually spoke for some time, and most of that conversation didn't make it into the short published piece. The editor did get the main points I made largely correct, though a few things got mangled. For example, I spoke about "forms of automatic identification, such as bar codes and RFID," which I think is how we wound up with FedEx "using automatic bar codes on every box." Yes, the famous automatic bar code.

But again, at a high level the article mostly reflected what I said. But in talking about the issue with some friends this past weekend, I soon realized the average person really has no idea how the FedEx system works, and generally doesn't see any reason why it couldn't be applied to immigrants or people generally. So taking it a little easy on this short work week, I am going to provide some insight as well as some contextual perspective.

I am going to start with the question of whether even if you could track people like boxes, should you? Obviously, this presents some ethical and "big brother" type issues that many would find highly objectionable.

In the early days of bar coding, in the late 1980s and early 90s, on more than one occasion I came out of conferences/trade shows focusing on auto ID (e.g., the old Scan Tech show) to find flyers on my car windshield. The flyers would contain an image of a bar code tattooed on a man's forehead or arm, accompanied by a dire warning about bar codes being the "mark of the devil."

Perhaps a little less sensational, a former Harvard professor named Katherine Albrecht gained some measure of fame with a book, roughly emerging with the Walmart RFID mandate in 2003-04, titled "Spy Chips: How Major Corporations and Government Plan to Track Your Every Purchase and Watch Your Every Move."

Part of the idea was that as retail goods were tagged with RFID, what you purchased could somehow be tracked at the POS and then even as consumers took their goods home. It led to several states passing legislation requiring retailers to kill or remove RFID tags at the time of purchase.

Of course today, most every purchase a consumer makes is already tracked by credit card companies, adding little value to redundantly doing it as well with RFID, but certainly there were some modest concerns about RFID and privacy early on, though I will note the Spy Chips web site seems stuck in 2007, even as finally now many years after the Walmart RFID program failure item-level RFID in soft goods retail is almost to the point of critical mass.

Interestingly, a program a few years ago based on having RFID tagged ID cards attached to the back packs of students in a San Antonio area high school gained national attention when one student refused to participate. Though school officials said the focus was simply on attendance and truancy, the protest by the female student that this was a general purpose tracking system that invaded her privacy touched a nerve, and the program was cancelled not long after as other parents got on the bandwagon.

Another tacking system of a sort can be found in some amusement parks that provide RFID-tagged tickets that enable parents to find out where their children should they become separated. I believe you have to "opt in."

Now having said all that, maybe we would put immigrants (Christie was referring of course to legal ones, by the way) in a class that such privacy concerns should be thrown out the window. You want to come here, we are going to track you. I was tangentially involved in a project at the LA County jail in the mid-1990s in which prisoners were given bar code wrist bands which were scanned wherever they went - to the cafeteria, in the exercise yard, etc. That way, the warden and others could know how many prisoners were where at any one time, and where any individual prisoner was and had been.

I believe some jails are doing similar things with RFID chips embedded in prison garb. I haven't heard anyone complaining of privacy issues relative to the prisoners.

So, let's assume we agree with the idea of tracking immigrants like FedEx packages is a good one, for various reasons. Could it be done?

The answer is No. Here is why.

First, the FedEx and most other tracking technology involved closed loop systems that operate in a highly controlled environment. FedEx employees scan a box when it is received or picked up. That say places that package in a specific FedEx truck. It is then scanned again when it arrives at a local FedEx station, then again when it is put on a truck headed to the airport, etc., as anyone who has ever tracked a package on-line knows.

But the system doesn't work outside that controlled environment. If a FedEx worker took a package outside the local station, FedEx has no idea where that box is. The entire system is based on FedEx employees scanning each box at defined entry and exit points. And importantly, the box appears to not mind being tracked.

So what type of process or system could possibly be developed to replicate that approach with a human being? If the idea is they will get a tap on the shoulder when it's their time to go, and they don't want to go, then obviously they would destroy the bar code or hide the fact that they have one. And where on earth would be the places that do the scanning, as an immigrant travels wherever they please?

Well, maybe we could embed a chip insted. We do it with dogs and cats, don't we? Well, yes we do, but the cats and dogs don't object. And that RFID system does not track an animal, it only identifies the animal should it become lost. The same principle would apply to people. Only special battery powered tags connected to satellites can track items (or people) in real time (such as are used on some truck trailers.). Trust me, you would not want one of these implanted in your body - and by the way, the battery needs frequently replaced.

If you used a small, passive tag such as us used on pets, (1) the chip could be relatively easily removed or damaged, or rendered useless by a metal sleeve/patch; and (2) it would take trillions of dollars to set up readers….what, everywhere? Protected and maintained how?

There have been some ideas around using the RFID tags on cars in many metro areas to track cars on major highways. This would take a change in the tag technology on cars now as well, cost a giant amount of money to put readers are the roads, only work on the roads, and only tell you where a car was, not who is in it.

Other than all those issues - piece a cake. We'll be tracking immigrants and maybe even the rest of us someday soon - not. Your best bet, Mr. Christie, is probably credit card tracking, and that won't get you very far. They could just pay with cash anyway. The automated license plate readers on cop cars could actually work as well - if a visa holder has overstayed and their license plate is read, they get pulled over - and "tapped on the shoulder."

Sadly, the ubiquitous iris scanning system in The Minority Report movie actually could likely work some day - let's pray we never go there, but even 50 years from now who knows.

Any reaction to Gilmore's summary of the immigrant tracking issue? What would you add? Will we have iris scanning some day? Let us know your thoughts at the Feedback button (email) or section (web form) below.