An anonymous TPM Reader gives us a look from the inside …
In your post, you ask “why wouldn’t [they] go back during the plot itself?” in regards to phone records.
I guarantee they did just that. I’ve worked for AT&T for close to 15 years now, spending most of my time in the network engineering side of the house. Call records on our network can be pulled for many, many months in the past. Getting these call records is probably one of the first things they did in the investigation so they probably weren’t part of this later
Verizon’s network is a little different than ours, despite this, they can probably see most of the same data we can. I can pull call records for a single number, which will give me phone calls, text messages, and internet data sessions. On phone calls & text messages, I can see the length of the call, the number of characters in a text message, the cell site the
call/text was placed on. I can also see the same information for the receiving end of calls or texts.
I can also pull all phone calls/texts placed on a single site for any given time. I would imagine that in a city like Boston, with a fairly high cell site density, you could narrow down the sender/receiver of a call/text to a square mile (or less) fairly easily.
Whenever something like this comes to light, the collective freak-out seems after the fact. Law enforcement already has access to every telecommunications switch through the CALEA program and the DCSNet. These things are real, I know for a fact that no new telecommunications switch is turned on until these things are in place and working.
“Privacy” is a thing of the past as far as electronic communications go – the only “protection” we have is the sheer volume of stuff flying around, but every year that protection gets less and less as computers get better at sifting through everything (and they’re really already “good enough” they just don’t have the horsepower to keep up in real time).