He also noted that it would be foolish to plan a terrorist attack or celebrate one online without using code words, encryption or anonymizer tools. But investigators, luckily, find a lot of foolish and sloppy criminals.
"I've done international IP theft cases and I've seen people write, 'I will take this part from my job and send it to China,' " said Jones. "I think people get the false feeling that everything is private even in an email forum or a social network. I think if I can't say this loudly in a room of lawyers, I shouldn't write it. Not everyone thinks that way."
He also said he would try to cull through direct message, or DM, exchanges on Twitter. People tend to think they're more private, not realizing that Twitter saves records of them.
According to Jones, federal or state prosecutors might be able to get a warrant to force Twitter to hand their records over if they have probable cause to look at certain DMs sent during a specific time frame.
DMs or Facebook pages might hold a wealth of information for investigators who are focusing on a certain person or for prosecutors who are preparing to put a suspect on trial.
"Facebook and Twitter will be really helpful once they've identified a suspect," Jones added. "Who are they talking to? Who are they identifying with? What messages have been sent?"
Some day, social media may become a predictive tool for law enforcement. Olds said. Government computers might analyze patterns of posts, frequency and word choice against profiles of people who have become increasingly unstable.
"I think that's the future of this," he said. "In the old days, if someone in the neighborhood started acting wacky, the neighbors would intervene or call the authorities. Now a lot of people interact more online than they do in person. I'd look to develop profiles and algorithms to see if I can spot people before they go off the deep end."
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