The term "reserves" refers strictly to petroleum which has been
discovered and is commercially recoverable. Oil that is off limits to
drilling by law is by definition NOT part of "reserves". I suspect
some of the anti-drilling bunch don't know that, but a lot of them do
and are being extremely disingenuous.
See
http://www.spe.org/spe-site/spe/spe/industry/reserves/Petroleum_Resources_Management_System_2007...
Note especially the last point in section
2.1.2, "Determination of
Commerciality"
* Evidence that legal, contractual, environmental and other social and
economic concerns will allow for the actual implementation of the
recovery project being evaluated.
That excludes from "reserves" any petroleum marked "off limits" by the
government.
If th drilling ban is lifted, and the other criteria are met, the oil
"magically" goes from being a "contingent resource" to a "reserve".