Some critics, however, think a mandatory system in which the drug agency had more police powers would be better.

Human rights groups and some members of Congress are also calling for a mandatory diamond-labeling system.

Finally, for fees that the mandatory system does not cover, there is a large range of private complementary insurance plans available.

"They usually have some very arbitrary, mandatory systems."

The Oregon vote was on whether to ban the phone company from establishing such a mandatory system of local metered service.

"But our guidelines' compliance rate is higher than the federal system, which had a mandatory system."

Connecticut has had a mandatory system since 1977.

The Food and Drug Administration wants to make that system mandatory.

The same mandatory system has been proposed for everyone, with reductions in emissions being based on market mechanisms.