The U.S. Supreme Court case London Assurance v. Companhia de Moagens do Barreiro in 1896 revolved around a dispute over insurance coverage for damages incurred by the Portuguese company, Companhia de Moagens do Barreiro (CMB), during civil unrest in Portugal. CMB had an insurance policy with London Assurance that covered losses due to "riots" and "civil commotions." When a political uprising occurred causing damage to CMB's property, they filed a claim with London Assurance who denied it on the grounds that the incident was not classified as either of those terms but rather fell under 'insurrection' or 'revolution', which were excluded from their policy. The court ruled in favor of CMB stating that while there is indeed a difference between riots/civil commotion and insurrections/revolutions, this distinction lies primarily in scope and duration rather than nature of action itself. Therefore, since the policy did not explicitly exclude losses resulting from larger scale disturbances such as revolutions or insurrections, London Assurance was obligated to cover CMB's claims.

In the dissenting opinion for London Assurance v. Companhia de Moagens do Barreiro, it was argued that the majority's decision to uphold a Portuguese court's ruling against an English insurance company was incorrect. The dissenting justices believed that the case should have been tried in England, where both parties had agreed to settle any disputes when they entered into their contract. They also disagreed with the majority's interpretation of international law and felt that it did not support upholding foreign judgments in cases like this one. Furthermore, they expressed concern about potential negative impacts on international commerce if contracts could be unilaterally altered by local courts without regard for previously agreed-upon terms.