A person commits the fallacy of.
This ad for Prop. 8, "Proposition 8 Vote Yes 11/4," commits the fallacy of equivocation. It confuses "right" in its its legal sense with "right" in its moral sense. The ad shows wedding cake figures of different couples and groups of people. The ad places in the mouths of the two grooms the assertion, "We have the right to marry our boyfriends," and, in the mouths of two brides, "We have the right to marry our girlfriends." Other "non traditional" couples assert their right to marry. The ad retorts, "That's not right." The rights the couples claimed were legal right, granted -- or denied -- by the legislature. The right of "That's not right" is moral: the producers of the ad do not assert that these marriages are not permitted by law, but that they contravene something above and independent of law.