Spyware and the Law
Attempting or gaining access to someone's computer without their consent or knowledge is criminally illegal according to computer crime laws, such as the United States Computer Fraud and Abuse Act and the United Kingdom's Computer Misuse Act.
Does this mean that spyware is illegal? Not necessarily. Though law enforcement has often pursued the creators of malware like viruses, spyware developers have been largely un-prosecuted under criminal law, though they occasionally do face lawsuits. Many spyware companies even operate as legitimate businesses.
Spyware creators remain largely untouched because of the way spyware generally finds itself on your computer. Though many people claim that they never authorized spyware access to their computer, spyware developers claim otherwise. Spyware that comes with the software that people download is normally mentioned in the license agreement that users must click consent to before installation. Most users ignore this agreement and just click "Yes" or "Agree" to proceed with the installation, and users who do read the agreement may not understand its implications. However, spyware producers argue that this is a legally binding contract, and when someone clicks consent to the license agreement they are consenting to the spyware. Hence, the spyware does not exist on people's computers without their consent, whether they read the license agreement or not, and it is therefore not violating any laws. Spyware may be annoying, but given that you clicked in agreement to a license in which it was mentioned, spyware producers argue that its existence on your computer is your own fault, and it is not against the law.
Despite this, some forms of spyware are against the law - for instance, spyware that is not mentioned in any sort of consent form upon installation. The U.S. states of Washington and Iowa have also passed laws criminalizing certain forms of spyware. These laws make it illegal for anyone other than the owner or operator of a computer to install software that monitors web browser settings, monitors keystrokes, or disables security software. Several bills have been voted on in the United States Congress including the Spy Block Act (Software Principles Yielding Better Levels of Consumer Knowledge) and the SPY Act (Securely Protect Yourself Against Cyber Trespass), both passed in 2004, and the I-SPY Act (Internet Spyware Prevention) passed in 2005 and reintroduced in 2007. These bills impose penalties and punishments the producers of spyware. They make it illegal to hijack control of a user's computer, expose users to pop-up ads that can't be closed, modify a user's personal settings, or download personal information without the user's consent.
So the moral of the story? Spyware is not illegal if you click consent to it in an end user license agreement during installation. So make sure you prevent spyware from contaminating your computer by reading all consent forms before you click. You may also want to learn how to remove spyware when it does show up on your computer.