If you know the heads or superintendents of the large agencies you will find that the "star" cases, of which they like to talk, are, for the most part, the pursuit and capture of forgers and murderers. The former, as a rule, are "spotted" and "trailed" to their haunts, and when sufficient evidence has been obtained the police are notified, and a raid takes place, or the arrest is made, by the State authorities. In the case of a murderer, in a majority of cases, his capture is the result of skilful "roping" by an astute detective who manages to get into his confidence. For example, a murder is committed by an Italian miner. Let us suppose he has killed his "boss," or even the superintendent or owner. He disappears. As the reader known, the Italians are so secretive that it is next to impossible to secure any information—even from the relatives of the murdered man.
The first thing is to locate the assassin. An Italian detective is sent into the mine as a laborer. Months may elapse before he gets on familiar or intimate terms with his fellows. All the time he is listening and watching. Presently he hears something that indicates that the murderer is communicating with one of his old friends either directly or through third parties. It is then generally only a question of time before his whereabouts are ascertained. Once he is "located" the same method is followed in securing additional evidence or material in the nature of a confession or admission tending to establish guilt. Having previously "roped" the murderer's friends, the detective now proceeds to the more difficult task of "roping" the murderer himself. Of course, the life of a detective in a Pennsylvania coal mine would be valueless if his identity were discovered, and yet the most daring pieces of detective work are constantly being performed under these and similar conditions. Where the criminal is not known, the task becomes far more difficult and at times exceedingly dangerous.
One of my own friends, an Italian gentleman, spent several months in the different mines of this country, where Italians are largely employed, investigating conditions and ascertaining for the benefit of his government the extent to which anarchy was prevalent. It was necessary for him to secure work as a miner at the lowest wages and to disguise himself in such a way that it would be impossible for anybody to detect his true character. Fortunately, the great diversity of Italian dialects facilitated his efforts and enabled him to pass himself off as from another part of the country than his comrades. Having made his preparations he came to New York as an immigrant and joined a party of newly arrived Italians on their way to the coal mines of West Virginia. Without following him further, it is enough to say that during his service in the mines he overheard much that was calculated to interest exceedingly the authorities at Rome. Had his disguise been penetrated the quick thrust of a five-inch blade would have ended his career. He would never have returned to New York. There would only have been another dead "Dago" miner. The local coroner would have driven up in his buggy, looked at the body, examined the clean, deep wound in the abdomen, shrugged his shoulders, and empanelled a hetrogeneous jury who would have returned a verdict to the effect that "deceased came to his death through a stab wound inflicted by some person to the jury unknown." My friend was not a professional detective, but the recital of his experiences was enough to fill me with new respect for those engaged in the "man hunt" business among the half civilized miners of the coal regions.
But the work of even the "national" agencies is not of the kind which the novel-reading public generally associates with detectives—that is to say, it rarely deals with the unravelling of "mysteries," except the identity of passers of fraudulent paper and occasional murderers. The protection of the banks is naturally the most important work that such an agency can perform.
The National Bankers' Association has eleven thousand members. "Pinkerton's Bank and Bankers' Protection" also has a large organization of subscribers. These devote themselves to identifying and running down all criminals whose activities are dangerous to them. Here the agency and the police work hand in hand, exchanging photographs of crooks and suspects and keeping closely informed as to each other's doings. Yet there is no official connection between any detective agency and the police of any city. It is an almost universal rule that a private detective shall not make an arrest. The reasons for this are manifold. In the first place, the private detective has neither the general authority nor the facilities for the manual detention of a criminal. A blue coat and brass buttons, to say nothing of a night stick, are often invaluable stage properties in the last act of the melodrama. And as the criminal authorities are eventually to deal with the defendant anyway, it is just as well if they come into the case as soon as may be. It goes without saying, of course, that a detective per se has no more right to make an arrest than any private citizen—nor has a policeman, for that matter, save in exceptional cases. The officer is valuable for his dignity, avoirdupois, "bracelets," and other accessories. The police thus get the credit of many arrests in difficult cases where all the work has been done by private detectives, and it is good business for the latter to let them know it.
One of the chief assets of the big agency is its accumulated information concerning all sorts of professional criminals. Its galleries are quite as complete as those of the local police headquarters, for a constant exchange of art objects is going on with the police throughout the world. And as the agency is protecting banks all over the United States it has greater interest in all bank burglars as a class than the police of any particular city who are only concerned with the burglars who (as one might say) burgle in their particular burg. Thus, you are more likely to find a detective from a national agency than a sleuth from 300 Mulberry Street, New York, following a forger to Australasia or Polynesia.
The best agencies absolutely decline to touch divorce and matrimonial cases of any sort. It does not do a detective agency any good to have its men constantly upon the witness stand subject to attack, with a consequent possible reflection upon their probity of character or truthfulness. Moreover, a good detective is too valuable a person to be wasting his time in the court-room. In the ordinary divorce case the detective, having procured evidence, is obliged to remain on tap and subject to call as a witness for at least three or four months, during which time he cannot be sent away on distant work. Neither can the customer be charged ordinarily for waiting time, and apart from its malodorous character the business is not desirable from a financial point of view.
The national agencies prefer clean criminal work, murder cases, and general investigating. They no longer undertake any policing, strike-breaking, or guarding. The most ridiculous misinformation in regard to their participation in this sort of work has been spread broadcast largely by jealous enemies and by the labor unions.
By way of illustration, one Thomas Beet, describing himself as an English detective, contributed an article to the 'New York Tribune' of September 16, 1906, in which he said:
"In one of the greatest of our strikes, that involving the steel industry, over two thousand armed detectives were employed supposedly to protect property, while several hundred men were scattered in the ranks of strikers as workmen. Many of the latter became officers in the labor bodies, helped to make laws for the organizations, made incendiary speeches, cast their votes for the most radical movements made by the strikers, participated in and led bodies of the members in the acts of lawlessness that eventually caused the sending of State troops and the declaration of martial law. While doing this, these spies within the ranks were making daily reports of the plans and purposes of the strikers. To my knowledge, when lawlessness was at its height and murder ran riot, these men wore little patches of white on the lapels of their coats so that their fellow detectives of the two thousand would not shoot them down by mistake."