Among the various arguments raised by critics of the growing impact of money in the electoral process, one of the most frequently made concerns the dangerous influence of corporations on the system, sometimes to the extent of their being described as the main source of corruption and bribery. Such an approach resulted in the passage of different laws and regulations by many states, aimed at restricting the financial activities undertaken by corporations before and during election campaigns. An example of such measures could be found in 1970s in Massachusetts, where the legislature established an act banning corporations from funding ballot initiatives if they had no direct interest in such a contribution. The controversy over the scope of the restrictions led to a lawsuit which ended in the Supreme Court in 1978, known as First National Bank of Boston v. Bellotti.

The First National Bank of Boston was subject to the restrictions provided by The Bay State law, and it could not freely participate in a campaign before a state referendum on taxation issues, so the bank's representatives challenged the state restrictions in court. On appeal, the issue was brought to the Supreme Court, which, in a 5–4 ruling, declared Massachusetts’ regulation unconstitutional as it violated the right of corporations to participate in various stages of the non-candidate election campaign. The majority opinion stated that corporations were protected by the free speech clause of the First Amendment, which was similar to the argumentation used by the Justices in the Buckley opinion. Despite the fact that the Bellotti decision referred mainly to state law, the argumentation used by the Justices became crucial for most of the 21st century cases concerning campaign finance, which cite Bellotti's reasoning almost as often as Buckley's.

MR. JUSTICE POWELL delivered the opinion of the Court