The trouble goes deeper than that.

The truth is that we are up against that most delicate of situations, the concrete adjustment of a theoretical individual right to a practical necessity.

The same difficulty has always existed and will always continue to exist whenever emergencies requiring prompt and decisive action arise or conditions obtain that must be handled effectively without too much discussion.

It is easy while sitting on the piazza with your cigar to recognize the rights of your fellow-men, you may assert most vigorously the right of the citizen to immunity from arrest without legal cause, but if you saw a seedy character sneaking down a side street at three o'clock in the morning, his pockets bulging with jewelry and silver! Would you have the policeman on post insist on the fact that a burglary had been committed being established beyond peradventure before arresting the suspect, who in the meantime would undoubtedly escape?
Of course, the worthy officer sometimes does this, but his conduct in that case becomes the subject of an investigation on the part of his superiors.

In fact, the rules of the New York police department require him to arrest all persons carrying bags in the small hours who cannot give a satisfactory account of themselves.