Weak respiratory muscles may suddenly fatigue, producing precipitous respiratory collapse. Elective intubation is preferable to emergency intubation or respiratory arrest. The standard 20/30 rule (FVC less than 20 ml/kg or NIF less than 30 cmH20) are the best indicators of the need for ventilator support.
Imminent lawless action is a term used in the United States Supreme Court case Brandenburg v. Ohio (1969) to define the limits of constitutionally protected speech. The decision overturned the decision of the earlier Schenck v. United States (1919), which had established clear and present danger as the constitutional limit for speech.
The Supreme Court established the separate but equal doctrine in the 1896 case of Plessy v. Ferguson, reasoning that state-mandated segregation did not violate the 14th Amendment as long as the separate facilities provided for whites and blacks were basically equal.