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 abstention doctrine was adopted by the Supreme Court to allow the federal judiciary to refrain from ruling on constitutional questions. Because it has no explicit source in federal or state laws, it is the exception to the general rule that a litigant may sue or be sued in federal court if the federal court has jurisdiction, or power to hear the case.