It's a gray area how much the rules permit you to use.
vague realm or area, ambiguous field; position which is not totally legal and not totally illegal, area known to be problematic but that is not dealt with specifically
grey area grey areas in AM, use gray area If you refer to something as a grey area, you mean that it is unclear, for example because nobody is sure how to deal with it or who is responsible for it, or it falls between two separate categories of things. At the moment, the law on compensation is very much a grey area. that gray area between blue-collar laborers and white-collar professionals