Eric is wrong. Sorry Eric.

There is no obfustication that blurs the distinction between spyware providers and vendors that make use of spyware advertising. They all may not quite understand precisely how it is illegal, but everyone knows just by the smell that there is something wrong with adware/spyware advertising.

The basic problem with spyware is fundamental. All spyware writes something to your hard drive. It may be an executable that displays an ad, a cookie that keeps track of your Internet activity, a change to your registry, or the contents of the ad itself. They all write something. And the writing is illegal unless they writer has your knowing and informed consent to write. Notice the "knowing and informed". They rarely ever do. At most there is some fine print buried in a web site's "privacy policy" or "terms of use" that vaguely suggests that you might be subjected in some unspecified form to on-line advertising. But, and here's the reason it is never "informed and knowing" consent -- by the time you read the fine print, the adware/spyware is already installed. You do not ever get the opportunity to actually say "no". Its the same as buying a bottle or water and discovering a message on the inside of the cap that says "by opening this bottle you give us permission to write our advertising message on the side of your car". The only thing you intended by opening the bottle was to drink the water. You would not be presume in any court to have given consent to writing on your car.

Spyware is usually installed in such a way that it is hard to find and harder to eradicate. Rarely does it come with an executable to uninstall it and even more rarely does it appear in the Windows Add and Remove program list. This is intentional. Spyware writers intend that it remain on your hard drive forever, popping up those ads on which the spyware company makes money. They intend that it be hard to find and harder to elininate. If enough spyware is written to your computer, it soon slows and dies.

The use of another person's personal property for one's own ends where the owner is substantially deprived of the use of the property, the property is damaged or the property is substantially interferred with is a common law tort. It is usually called "trespass to chattels". If this seems to you to describe the effect of spyware on your computer, you're dead right. Writing spyware on your computer is a tort, actionable at law. You can get damages and an injunction prohibiting a spyware company and the vendor using the spyware company from ever writing on your computer again.

It may also be a crime. You well know that if I write my ad message on the side of your car, it's vandalism (sometimes called graffiti or malicious mischief). I could go to jail.

How does this differ from writing on your computer hard drive? Both the car and the hard drive are your personal property. You did not give me company permission to write its add material. So what is the difference? A lot of wind has gone into an effort by spyware companies to distinguish a difference, but in fact there is none.

Any crime is also a tort, and, again, you can sue and recover damages and/or get an injunction.

That's the fundamental problem with adware/spyware. The process is illegal. All the spyware companies, vendors who hire spyware companies, and web sites that permit spyware to be downloaded all know it is illegal. They just hope you don't find out. But now you know, so hie down to the courthouse and sue the bastards.