From a layman’s view what one accesses on the internet is under one’s control. To the contrary that is not true. When you visit a webpage you connect to two or more other servers that collect your information and also download files onto your hard drive. These files can be anything from cookies to help you login to trackers that track your internet habits or even images.
Consider watching a video on www.youtube.com. Even before you press the play button the video is downloaded to you hard drive. An average computer user will not be able to find the where the video is located, but a computer forensics technician, or an Information Technology student will be able to find the video.
If such a video was a movie leaked to the internet, you are in possession of the said movie. Does that constitute legal possession. One would say no.
The most important quote is
Merely viewing in a web browser an illegal image stored in a remote location on the Internet does not establish the level of control necessary to find possession. Neither does creating a “favourite” or an “icon” on one’s computer. In order to commit the offence of possession, as opposed to the offence of accessing of [censored], one must knowingly acquire the underlying data files and store them in a place under one’s control. It is the underlying data file that is the stable “object” that can be transferred, stored, and possessed. The automatic caching of a file to the hard drive does not, without more, constitute possession. While the cached file might be in a “place” over which the computer user has control, in order to establish possession it must be shown that the file was knowingly stored and retained through the cache.
While the precedence on possession of material available on the internet had to be set in an infamous case. One must believe that laws should be reflective of the society.