[nkrumm]

Exactly. The phrase "probable cause" can (and should) be directly related to the probability of a false positive; in the context of virtually unlimited 'data dumps', this paradigm must be adapted to reflect the probability of a false positive in a multiple-testing situation.

The FBI in this case was successful because they had 4 (or 3) towers; with only two it is likely they would not have been able to hone in on the criminals as quickly as they did. It's perhaps even possible to calculate what the chance of success is, and establish guidelines for release of data based on this (e.g., minimum 4 towers). Also, probability would have to be taught in law schools.

[rayiner]

> Also, probability would have to be taught in law schools.

The first couple of weeks of my Evidence class was a crash course in probability and Bayes' rule. Our final exam had an entire section on it. I'd imagine you can still get through law school without learning probability, but it's getting increasingly harder as Evidence is reformulated on probabilistic grounds, just as Torts was reformulated on economics grounds in the 1960-1970's. Today you probably can't get through a Torts class without learning about Pareto efficiency or Coase theorem, etc. Also, empiricism is a dominant academic trend right now in legal academia, and it heavily relies on statistical approaches.

[nkrumm]

Very interesting, thanks for that. I admit I had no idea if statistics was part of the law curriculum or not. Glad to hear it is!

[hga]

As long as you're talking about an investigation to develop leads, if the investigators have a clue false positives aren't necessarily going to be bad. In this investigation, they didn't just go arrest the people associated with the two numbers they found, they got the metadata for the two numbers and saw enough additional correlations they could be pretty sure they'd found their men, especially with the added highly suspicious behavior. Presumably a few false positives wouldn't have panned out after their metadata was examined, e.g. in this one's second stage they went from 3 out of 4 to "most of the 16 the bank robberies under investigation".

[nkrumm]

Maybe in this case the false-positives were easily filtered out. However, if the initial search is too broad, and too un-specific, incorrect assumptions and false positives are certain to occur due to human error, prejudice or carelessness. This is one of the primary reasons why the "I have nothing to hide" argument in favor of increased surveillance is inadequate-- you may have nothing to hide, but errors not in your favor can unjustly cast you as having something to hide.

[JoeAltmaier]

NO the primary reason is, you have no privacy. Its a ticking time bomb - nothing you do or say can every be private, which means forgotten except by your intimates.

I liken constant surveillance to a bomb planted in your body. If you have nothing to hide, then no problem right?

[hga]

Note, I'm not an advocate for our current "you have no privacy to speak of" regime. On the other hand, short of our government going Godwin (in which case the remedies aren't to be found here), the American people aren't going to agree to fixes that preclude this sort of investigation.

Anyway, a point I'm making is that law enforcement officers might cast a wide net, but they really want to find the right fish. If for no other reason than that they then have to prove it all in court. The screw case it sounds like you're concerned with is the "find the person, then find a crime" type. If I'm wrong, could you sketch out an abusive scenario?

[nkrumm]

I agree, of course law enforcement wants to find the right fish. Short of a few bad apples (more food analogies!), I don't think that their intentions are malicious (i.e., find a person then find a crime). Instead, I'm concerned about a situation where pressure exists to "find the person" (think Boston Marathon bombing)-- and then shortcuts are taken. Granted, this can happen in a world w/o excessive surveillance also, but its far easier to find a fitting suspect when 100k people are in your net. Those suspects-- ideally-- would be crossed off the list asap, but not before significant harm could be done. Thanks for the interesting discussion!

[hga]

You haven't sketched out a scenario were particularly bad things happen. Yeah, getting arrested and subject to an abusive dwelling search are bad, and due to the poor arms handling of police potentially more than significant harm, but, again, presumably the police would find no evidence to back it up and move to the next set of suspects.

A better example would be the FBI's "investigation" of the post-9/11 anthrax attacks. Neither of the suspects they harassed within an inch of their lives and beyond for the second were guilty, although I think the remedy there is to abolish such politicized "law enforcement" agencies. Whatever their tool set it, they'll abuse it and innocent citizens.