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 United States Supreme Court, in 1968 decided the case of Haynes v. United States in favor of the defendant, which effectively gutted the National Act of 1934. As one could possess an NFA firearm and choose not to register it, and not face prosecution due to Fifth Amendment protections, the Act was unenforceable.