Citizens United v. FEC (2010)
The Supreme Court ruled 5-4 that corporations and unions may spend unlimited money on independent political advertisements. The decision struck down the federal ban on corporate electioneering and opened the door to super PACs funded by unlimited individual donations.
Super PACs appeared within weeks and reshaped the 2010 midterms as outside groups outspent party committees in key races.
Independent expenditures became the dominant channel for political money; federal limits apply only to direct contributions, leaving the same loophole San Francisco still uses.
The same legal structure allows Larsen's $500,000 check. Money routed through an independent committee faces no cap, so candidates stay formally independent while a billionaire funds their path to office.
