What gives the BJCP the authority to define beer styles?

It’s part of the BJCP’s Mission Statement. One of the purposes of the BJCP is to promote beer literacy, which includes understanding more about the world’s great beer styles. The BJCP has been operating since 1985 and has been publishing guidelines for much of that history.

We have spent considerable time researching world class beer examples, visiting renowned breweries, talking with noted authors, and searching key reference materials for information on beer styles. We have collected this information into our guidelines as a way to reduce the amount of time, effort and variability in learning this knowledge.

We hope you find our guidelines useful, but you are free to use your own research and believe what you want. However, if you enter a beer in a AHA/BJCP-Sanctioned Competition, know that these guidelines will be used as the benchmark against which your beer will be judged.