In the case of Chicago Mercantile Exchange v. Deaktor et al., the U.S Supreme Court was tasked with determining whether a federal district court could exercise jurisdiction over an action brought by a commodity exchange against its members under Section 4b of the Commodity Exchange Act. The plaintiffs, who were members of the Chicago Mercantile Exchange (CME), had allegedly violated trading rules and regulations set forth by CME. They argued that their actions fell within normal trading practices and thus did not violate any laws or regulations. However, CME disagreed and sought to enforce penalties for these alleged violations through legal means. The Supreme Court held that federal courts do have jurisdiction in such cases as they involve questions related to federal law - specifically, whether certain activities constitute "manipulative or deceptive" conduct under Section 4b of the Commodity Exchange Act. This decision affirmed that exchanges like CME can seek enforcement of their rules through federal courts when necessary.

In the dissenting opinion for Chicago Mercantile Exchange v. Deaktor et al., Justice Douglas argued that the majority's decision to allow exchanges to self-regulate without government oversight was misguided and potentially harmful. He contended that such a laissez-faire approach could lead to abuses of power, as it would enable dominant market players to manipulate prices and engage in other anti-competitive practices unchecked. Furthermore, he expressed concern about conflicts of interest arising from allowing exchanges both to make rules governing trading activities and enforce them themselves. In his view, this arrangement could result in biased enforcement favoring exchange members at the expense of non-members or smaller traders. Therefore, he believed that more robust governmental regulation was necessary to ensure fair competition and protect consumers' interests.