“People versus Candido.”  Now why did he kill?  I remembered the Italian perfectly.  He killed his friend because the latter had been too attentive to his wife.  “People versus Higgins.”  Why did he?  That was a drunken row on a New Year’s Eve within the sound of Trinity chimes.  “People versus Sterling Greene.”  Yes, he was a colored man—­I recalled the evidence—­drink and a “yellow gal.”  “People versus Mock Duck"-a Chinese feud between the On Leong Tong and the Hip Sing Tong—­a vendetta, first one Chink shot and then another, turn and turn about, running back through Mott Street, New York, Boston, San Francisco, until the origin of the quarrel was lost in the dim Celestial mists across the sea.  Out of the first four cases the following motives:  Jealousy—­1.  Drink—­1.  Drink and jealousy—­1.  Scattering (how can you term a “Tong” row?)—­1.

I began to get interested.  Supposing I dug out all the homicide cases I had ever tried, what would the result show as to motive for the killing?  Would drink and women account for seventy-five per cent?  Mentally I ran my eye back over nearly ten years.  What other motives had the defendants at the bar had?  There was Laudiero—­an Italian “Camorrista”—­he had killed simply for the distinction it gave him among his countrymen and the satisfaction he felt at being known as a “bad” man—­a “capo maestra.”  There was Joseph Ferrone—­pure jealousy again.  Hendry—­animal hate intensified by drink.  Yoscow—­a deliberate murder, planned in advance by several of a gang, to get rid of a young bully who had made himself generally unpleasant.  There was Childs, who had killed, as he claimed, in self-defence because he was set upon and assaulted by rival runners from another seaman’s boarding house.  Really it began to look as if men killed for a lot of reasons.

One consideration at once suggested itself.  How about the killings where the murderer is never caught?  The prisoners tried for murder are only a mere fraction of those who commit murder.  True, and the more deliberate the murder, the greater, unfortunately, the chance of the villain getting away.  Still, in cases merely of suspected murder, or in cases where no evidence is taken, it would be manifestly unfair arbitrarily to assign motives for the deed, if deed it was.  No, one must start with the assumption, sufficiently accurate under all the circumstances, that the killings in which the killer is caught are fairly representative of killings as a whole.

All crimes naturally tend to divide themselves into two classes—­crimes against property and crimes against the person, each class having an entirely different assortment of reasons for their commission.

There can be practically but one motive for theft, burglary, or robbery.  It is, of course, conceivable that such crimes might be perpetrated for revenge—­to deprive the victim of some highly prized possession.  But in the main there is only one object—­unlawful gain.  So, too, blackmail, extortion, and kidnapping are all the products of the desire for “easy money.”  But, unquestionably, this is the reason for murder in comparatively few cases.