Professor Kerr discusses the Warrant Clause and how it applies to national security investigations.  The Supreme Court has declared that domestic searches without judicial permission are per se unreasonable, but this is not the case in national security law.  Kerr suggests this may be a result of separation-of-powers concerns as courts are hesitant to infringe on the President’s national security powers.  However, Kerr mainly argues that the reason the Warrant Clause is limited in national security investigations is because courts recognize they are ill equipped to decide when a warrant is reasonable, given the context of national security investigations. Because courts lack expertise in such investigations and given the sensitive nature of national security investigations, courts have taken a narrow interpretation of the Warrant Clause in national security cases.