If the Feds are investigating you can they read your emails in Yahoo if you have erased them already and could they get your conversations in Yahoo Messenger even if you didn't save them?

Yes.

Answer

A good rule of thumb regarding email, or anything else you send over the net, is this: If you can't bear having it read aloud in a court of law, don't send it.

Answer

The above is good advice, but I'd take it a step farther. If it is private and you don't want anyone/everyone to see it, NEVER send it in an e-mail or IM, do not talk about it in chat rooms (chats can be saved), do not post it on message or discussion boards. In fact, you'd do well not to even save it on a disk, CD or your computer if it is something the Feds would be interested in.

I learned this years ago: If you don't want someone else to see/read it, don't write it down. I learned this the hard way after having my mother read my diary when I was a teenager, then again years later, when my husband started reading my personal journals.

If the Feds are indeed investigating you, even hard copies (pen and paper copies) could become open to scrutiny if they find enough evidence to merit a warrant for your home.

This advice has apparently come a bit too last if you're already under investigation but the best way to protect your privacy and stay out of trouble is to simply avoid questionable activities. It's not hard, hundreds of millions of people manage to do it their entire lives.

Answer

in the short form

Yes

in the long form

you could encrypt everything you do

but it wont help your case to look like an very paranoid person

as if you had something to hide

you could also find a way to flip a switch to destroy/mame/melt/ damage until it looks like dust your computer

but sooner or later you could slip up and get busted

so in conclusion

attempting to evade the law is a stupid and immoral idea

Answer

Yes.

Calea, Patriot Act, Carnivore, Echelon, Matrix, Safeback, Snapback, keyloggers, pen registers, Microsoft/AT&T backdoors, FBI staffed computer forensic labs, etc. are all REAL.

Your ISP has a record of every single thing you have typed on record.

and...don't forget to point your webcam at the wall......

Here is a link to all cyber laws:

http://www.ccmostwanted.com/CP/LE.htm

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