Have you ever faced a pop-up that wouldn't go away? You try clicking it closed and another pops up in less than a nanosecond. You reboot the system, annoyed that your anti-spyware program let something slip through.

That's a hassle, sure -- but chances are, your experience won't land you in jail.

A teacher's worst nightmare

Julie Amero, a substitute teacher in Norwich, Connecticut, has been convicted of impairing the morals of a child and risking injury to a minor by exposing as many as ten seventh-grade students to porn sites.

It's a short story: On October, 19, 2004, Amero was a substitute teacher for a seventh-grade language class at Kelly Middle School. A few students were crowded around a PC; some were giggling. She investigated and saw the kids looking at a barrage of graphic, hard-core pornographic pop-ups.

The prosecution contended that she had used the computer to visit porn sites.

The defense said that wasn't true and argued that the machine was infested with spyware and malware, and that opening the browser caused the computer to go into an endless loop of pop-ups leading to porn sites.

Amero maintains her innocence. She refused offers of a plea bargain and now faces an astounding 40 years in prison (her sentencing is on March 2).

Just the facts

I'll admit all my don't haves right away: I don't have access to court records; I don't have first-hand evidence of what occurred; and I haven't examined the computer's hard drive myself.

What I do have is a working knowledge of spyware and plenty of experience cleaning infected PCs.

I also have a copy of the report written by computer forensic specialist W. Herbert Horner, the expert witness who testified in Amero's defense. You can read it, too; it's on the NetQos site .

Proof, speculation, and a not-very-good defense

Horner made an image of the computer's hard drive. He saw that there was no firewall and that the antivirus program was outdated. He also found 42 active "spyware/adware tracking cookie/programs." Most important, Horner said that 27 of the spyware apps were accessed before Amero had access to the computer.

To me, the implication is clear that Amero hadn't used the PC for browse for porn, as the prosecution claimed.

The defense wanted Horner to have Internet access at the trial in order to re-create what happened to Amero in the classroom. The prosecution objected, claiming they hadn't had full disclosure of Horner's examination.

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