Last week, a federal judge in Texas refused to authorize the government to hack a computer suspected of criminal use, including controlling the computer's camera. The government had sought a warrant to "surreptitiously install software designed not only to extract certain stored electronic records but also to generate user photographs and location information over a 30 day period." Noting the high standards for a warrant for wiretaps and video surveillance under the federal rules and the Fourth Amendment, Judge Smith determined that the government had not met its burden.
Judge Smith looked carefully at the legal issues, but you can't be sure that every judge will be familiar enough with the law and technology to stand up to overly broad government requests. At the same time, you may be concerned that malicious hackers or rogue government entities will take control over your camera. But you can protect against the effects of webcam hacking with a few easy steps.
UPDATE: EFF has made it even easier for you to guard your webcam with these Laptop Camera Cover Stickers, featuring an ultra-removeable adhesive that won't leave any residue. But if you want to engineer your own cover, read on!
Use the scissors to cut a small rectangle out of the sticker, sized to fit well on your laptop. While a post-it on its own can easily cover the camera, some post-its are more translucent that others. Putting a black vinyl EFF sticker can give you that extra confidence, and show off your commitment to privacy and security.
Place the EFF sticker above the sticky portion of the post it, and cut away the excess. Post-it notes use a low-tack, reusable, pressure-sensitive adhesive, which is better for removing and replacing whenever you need to use the camera.
Now add your camera protector to your laptop, and voila, you have blocked the ability of third-parties to take your picture through surreptitious malware on your computer.
While this technique can give you control over your own camera, and ensure that it is not being used when you are not aware, please keep in mind that malware, whether installed by the government or third-parties, can still own your computer and provide the attacker with logs of your activity, your location and even the keys you press. These measures act as a kind of band-aid against surveillance (and some people use a band-aid for this purpose). It's a simple step that will mitigate the harm, but not a complete privacy solution.