Colour state other than clouds or low visibility (e.g. ice or other obstructions) then the word BLACK is written in full and placed immediately before the actual colour state (e.g. BLACKWHT). The colour state may be appended to a METAR report. A short period forecast called a "TREND" which covers the following two hours from the observation may also be added, often with reference to the colour state. The following criteria are used to determine the colour state: Colour state Colour states is a system used for quickly showing meteorological conditions. Meteorological colour states are determined by the relevant worst condition from
Expert witnesses in English law Expert witnesses in English law The role of expert witnesses in English law is to give explanations of difficult or technical topics in civil and criminal trials, to assist the fact finding process. The extent to which authorities have been allowed to testify, and on what topics, has been debated, and to this end a variety of criterion have evolved throughout English case law. Generally, witnesses are not permitted when giving evidence to tender their own opinions as fact. The reason for this is that to allow opinion evidence would be to usurp the fact finding duties of either a