The number one problem with presenting video evidence in legal situations is misinterpretation. Even though the video evidence may seem visually compelling, mistakes are very often made which affect the outcome of a case. For example, the interpretation of motion in CCTV can be problematic given the varying frame rates one encounters. Additionally, compression technology used to digitize video and transmission errors it sometimes suffers from can introduce visual changes which affect the interpretation of motion. Even the picture content itself is often not what it seems. For example what may seem real and tangible might be a shadow or digital compression artifact. Also, these two issues can interact to compound the challenge of correctly interpreting the video. As a video analyst I consider the first step in any video examination is to determine the reliability of the key aspects of evidence video such as motion or picture elements in the area of interest.