I know this sounds very arrogant, but I would love to see trials change so you're actually judged by your peers instead of members of the public, so for example doctors by doctors, network admin by other network admin, and such. That way you can get a bunch of people who know how far this person has stepped out of line. .
You're not the first to think of such an idea, it actually has a name. I learnt about it way back when I was doing Legal Studies as a subject during my VCE (Victoria, Australia's version of your typical high school certificate).
So anyway, we did a unit on Juries and the different types and how we ended up with the one we have today in our legal system. One of the jury types that were turned down was exactly how you described and I recall thinking "that actually sounds like a good idea". The reason that it's not used (at least, according to my text book) was that juries who were in the same line of work as the defendant tended to be unfairly harsher then your stock standard jury.
For example, say that in this case, all the jury members were IT networking professionals (yes, I realize in this case one of them did have a CCIE). There's the tendency that all the jury members would think "Well, this guy just brought down our entire industry and did something I would never do -- let's give him [insert harsher verdict/sentence than a standard person would give]"
I know, for example, if I were put on a jury for some guy who allegedly made a botnet and was hiring it out for the highest bidder, I would certainly be giving a very harsh verdict/sentence.
That all said, I can't for the life of me recall what this jury type was called, and my 30 seconds on Google didn't find a result, so please take this post as [citation needed].