Board Examiners are those who "sit" at the Board of Review opposite of the scouts. Each scout must prove to them that he has earned his Merit Badge or Rank or else he will fail the Board and have to try again at a later date.
The examiners are in control of everything that occurs at a Board of Review. They send for the next scout to come up. They return the scout's salute and begin (or send him back to repeat the introduction if he made a mistake). They have the deciding factor in which badge or rank to do first. They decide which requirements to test. Ultimately they decide whether the scout passes or fails.
The Board can be very intimidating for new scouts (not necessarily a bad thing) but for a scout who is genuinely prepared for the Board it is nearly impossible to fail. Some examiners are much more strict than others but no one is there to try and sabotage rank advancement.
During the examination, the examiners have access to the materials (books, worksheets, etc.) from which to quiz the scouts. Not all requirements need to be touched in depth (or even touched at all) and the examiners will likely go over the requirements out of order. Often, the examiners will ask questions that are beyond the scope of the required material. This may be to see how knowledgeable the scout truly is or even to search for the boy's opinion rather than the regurgitation of facts.
Being an ExaminerEdit
The composition of the examiners varies widely from Board to Board and it largely dependent upon who is actually available to "sit" on the Board. Examiners are expected to have basic knowledge about Scouting and the Troop but they need not have any specific background in the subject of a specific Merit Badge (It's actually better for scouts not to have to demonstrate knowledge of Aviation Merit Badge to a Pilot). Boards can be made up of Assistant Scoutmasters, Troop Committee members, Man Scouts, parents, and even senior staff if there is a desperate need.
Each Board of Review is actually made up of several separate Boards which can range from only two Boards to seven or eight at a particularly massive summer BOR. Each separate Board is typically made of two examiners that are often paired so that their fields of knowledge and experience compliment each other rather than simply overlapping.