Tower data analysis, second opinions and standards?

Greg,

I originally intended to send this to you as an email, but I thought the open discussion might prove to be educational? Some of what I am talking about has already been discussed in an earlier post, but I thought I would revive it.

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The other day I received some CDR’s with cell site data on a case I am currently working. Prior to receiving them I had a preconceived idea of what the data would indicate. When I received the data, plotted my towers and sectors they seemed to indicate something different than what my preconceived opinion was. I don’t believe my victim in this case is lying, but when looking at the data it seems to tell a different version of how the handset moved on the day in question.

One of the first things I have had to factor in is that I don’t live in a flat part of the US. I live in an area with lots of hills and small mountains. I was fortunate enough last year to be present during a drive test and was able to watch a CDMA handset’s signal jump from tower to tower. I must say it was an eye opener as the signal did some crazy things.

I then thought about what I could do to get a second opinion, second set of eyes on the data or some sort of peer review?

I spoke with a friend of mine the other day who is an RF expert. I don’t know the specifics of what his resume is, but I do know that he has over 30 years experience in the Air Force with RF communications and has testified in State and Federal Court. He does have an understanding of cellular technology and the dangers and pitfalls that come with “drawing circles.”

I told him I would send him the data, would not tell him about the case (so as not to taint his examination with my preconceived ideas) and maybe we could compare notes next week. Keep in mind that I don’t have the resources available to pay someone to review the data.

I was wondering what protocols or best practices might be in place in the UK to verify ones findings, either through a second opinion or some sort of peer review? What are they doing at Scotland Yard or at some of the larger departments? Is there a specific standard that officers or detectives are trained to in the UK?

From what I understand the National Technical Investigators Association www.natia.org is in the process of creating some sort of certification in cellular technology. If this is correct I’m sure some understanding of cellular networks, factors affecting signals, mapping and interpreting the data would be part of that curriculum.

With training budgets already strained most departments can only find enough resources to send one officer or investigator to a class at a time. Upon completion the officer may return really knowing their stuff, or the old adage “In the valley of the blind the one eyed man is king” may apply?

This is where I’d like my US based counterparts to respond.

What are your departments doing, or what are you doing on your own? Have you developed resources from previous training you attended to have records or your findings reviewed? Do you share the facts of the case with the individual evaluating the records or do you try to hit the high points and stay away from specifics? I believe any input would be appreciated by all.

Let the discussion begin!