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Pinkerton's National Detective Agency Records in the Manuscript Division

Highlights

Below are some intriguing highlights from the Pinkerton's National Detective Agency Records in the Manuscript Division.

Please Note: The Pinkerton's National Detective Agency Records at the Library of Congress contain little information about individual Pinkerton's employees. The records include business and family correspondence, biographical and genealogical records. Administrative records consist largely of procedural guidelines and training manuals. The criminal case files include correspondence, reports, photographs, legal documents, and printed matter for a limited number of individual cases.

The Criminal Case File series in the Library’s collection represents only a fraction of the company's business. Branch office files are not generally included in Pinkerton's records. Furthermore, many family and business papers burned when the agency headquarters was destroyed in the Chicago fire of 1871. The records at the Library of Congress primarily reflect activity in the New York and Chicago offices and are often limited to the company's more famous cases.

Criminal Cases

Although the Criminal Case File series represents only a fraction of the company's total business, these cases received extensive publicity even many years after being closed. The Pinkerton archive was the source for many popular "true western" and detective stories. As a consequence, newspaper and magazine articles often dominate the case files. Most cases, however, contain at least some documentation created during an investigation, such as correspondence, reports from operatives, mug shots, reward notices, and wanted posters. Some cases include legal documents and police and prison records such as Bertillion charts, which recorded bodily measurements and physical descriptions of suspects as the primary means of identification before fingerprinting became standard in the twentieth century.

Pinkerton's officials wrote articles about their important criminal cases for exhibitions, publicity, or simply to create a narrative account of events. Records identified in the Criminal Case File as essays and notes were usually created by the agency itself. However, the agency did hire professional writers, or allowed them access to the “secret archive,” as this collection was sometimes styled, and drafts of their essays may also be included in the files.

Cases are arranged alphabetically by the name assigned by the Pinkerton agency. Some cases are identified by the name of the criminal or gang of criminals. Pinkerton's used the legal name of the criminal, in so far as it could be established, and not a more commonly known alias. Other cases are identified by the name of the victim, such as a train, bank, jeweler, or murder victim. For instance, the serial-killer Herman Mudgett (also known as H. H. Holmes) was first investigated by Pinkerton's for insurance fraud after he filed a claim when his business partner, Benjamin Pitezel, appeared to have died in an office fire. The case is identified as the Pitezel murder, but the file more fully documents Mudgett's sensational life of crime. Crimes committed by a group of cowboy criminals are subsumed under the entry for Butch Cassidy and the “Wild Bunch,” the name given to the cattle thieves, bank and train robbers, holdup men, and general outlaws congregating in the Hole-in-the-Wall country of Wyoming where, commencing in 1897, they came under the leadership of Robert Leroy Parker, alias Butch Cassidy. Butch Cassidy and the Sundance Kid have been identified in the files by their criminal names, an exception to the usual practice since these names conform to name authority files established at the Library of Congress.

Since gang membership was not necessarily fixed or exclusive, records for some criminals may be found in several case files. Card indexes created by Pinkerton's to cross reference gangs and individuals are in the Administrative File. The indexes sometimes cite a “binder number,” the numerical filing system first established in the 1930s when a Pinkerton's manager, Ralph Dudley, began compiling the corporate archive by gathering case material into expandable binders. The case files have been reorganized in an alphabetical arrangement, but if the index refers only to a binder number, the numerical list of binder titles at the beginning of the index can be consulted to determine the case name.

Marion Hedgepeth ID card, 1892. Pinkerton's National Detective Agency Records, box 113, folder 10. Library of Congress Manuscript Division.

Even though the Criminal Case File series only represents a small fraction of the work undertaken by the Pinkerton agency during its century of ownership by the Pinkerton family, and despite many individual case files containing primarily newspaper clippings or copies or records, there are still many highlights to be found in the Criminal Case File series. One example is the case file for the Marion Hedgepeth gang, who robbed trains in the 1890s (see box 113). The case file contains notes, correspondence, and essays about the Hedgepeth gang, photographs and physical descriptions of the men, references to publications about the case, contemporary newspaper clippings, a 1959 True Western Adventures magazine article ("Have Derby--Will Kill!"), and a wanted poster. Of particular interest is the correspondence between Marion Hedgepeth and William A. Pinkerton, in which Hedgepeth appealed to Pinkerton for help in following a more honest path after his release from prison, which resulted in Hedgepeth's temporary employment as an informant for the Pinkerton agency. Unfortunately, Hedgepeth soon returned to his criminal ways, which is addressed by correspondence in the file. The Hedgepeth file also reveals rivalries within the law-enforcement communities, especially with regard to claiming credit for apprehending criminals. "[St. Louis Chief of Detectives] Desmond is nothing but a pin-head and so are nearly all the others who steal credit for everything," William Pinkerton exclaimed to his brother on July 22, 1906, in relation to a newspaper article about the Hedgepeth case. "Here is a case where he had absolutely nothing to do with it and yet they leave out everybody but themselves." Robert Pinkerton sympathized, but made peace with others stealing the limelight.

Letterbooks

Incidents of the war, group at Secret Service Department Headquarters, Army of the Potomac, Antietam. [Allan Pinkerton is the bearded man in the center, standing to the left of the tentpole] October 1862. Library of Congress Prints & Photographs Division.

A highlight in the Administrative File series is eight letterpress copybooks, supplemented by three investigative field reports. The first two letterbooks concern Allan Pinkerton's activities as head of the secret service for the Army of the Potomac, and reflect the scope of activity performed during the early inception of this unit. The copybooks consist mostly of outgoing correspondence and reports addressed by Pinkerton under his wartime pseudonym, Major E. J. Allen, to various government agents and officials, including George B. McClellan and Andrew Porter. These reports summarize field investigations gathered by Pinkerton's operatives, and largely concern incidents of sabotage and espionage occurring in the Washington, D.C., area. Copies of incoming letters are included, as are private letters written under Pinkerton's own name. In an October 6, 1861, letter to John Dewe, Pinkerton describes his early years in his native Scotland and the influence of those experiences on his commitment to the Union cause and the abolition of slavery.

The letterbooks of George H. Bangs, the longtime general superintendent of the New York office, document the day-to-day functions of the agency. Bangs's letters to Allan Pinkerton relate the progress of specific investigations and details of general administration. His letters to district superintendents concern operational policy ranging from office management to investigative procedures.

The letterpress copybooks containing Allan Pinkerton's outgoing correspondence (boxes 47-48/reel 3) include letters of a more private nature, some of which reveal tensions with his sons William and Robert, especially over "Willie's" behavior in the 1870s. Although part of the Administrative File series, Pinkerton's personal letterpress books yields insights into members of the Pinkerton family, which informed their operation of the Pinkerton agency.

Molly Maguires Case

The investigation of the Molly Maguires was the last important case that Allan Pinkerton personally supervised. The Molly Maguires were a secret organization of Irish immigrant coal miners who used violence and intimidation to battle low wages, poor working conditions, and ethnic discrimination in the anthracite coal fields of Pennsylvania. A report dated January 24, 1875, and sent to Franklin Gowen, president of the Reading Railroad, by Benjamin Franklin, superintendent of the Pinkerton office in Philadelphia, recounts the daily movements of James McParland, the Pinkerton operative who infiltrated the Molly Maguires. This report and two others concerning labor unrest and unionization in the Pennsylvania coal region were microfilmed with the letterpress copybooks contained in the Administrative File series (box 48/reel 3).

Additional material on the Molly Maguires can be found in the Criminal Case File series (boxes 140-142). Very few of the items in the Criminal Case File series are original contemporary documents, although the files do contain some transcripts purportedly to have been made of original sources. The Molly Maguire folders contain correspondence, notes and essays, newspaper and magazine articles, and photographs (some of locations in the coal region in the twentieth century). Despite the near absence of period documents about the Molly Maguires in the case file, the materials demonstrate the continued public interest in aspects of the case into the mid-twentieth century.

Administrative Files

Harris & Ewing. "Pinkertons" tell all, Washington, D.C. Sept. 25. Robert A. Pinkerton, (left) youthful president of the Pinkerton Detective Agency, and Asher Rossiter, as they appeared before the Senate committee investigating strike-breaking. September 25, 1936. Harris & Ewing Collection. Library of Congress Prints & Photographs Division.

The Administrative File series includes rules of conduct and a code of ethics Allan Pinkerton communicated to his employees in essays entitled, “General Principles.” Pinkerton determined that the agency would not undertake an investigation on behalf of a defendant in a criminal case, would not conduct investigations involving the activities of public officers, or investigate parties suing for divorce. Pinkerton's agency did investigate labor unrest and was involved in strikebreaking at mining operations and related industries, though very little documentation of these activities is in the collection. Agency policy stated that records of such operations were returned to clients.

While few items in the collection relating to the Civil War are original to the era, other than the letterpress copybooks from Allan Pinkerton's time with the Army of the Potomac, most of the Civil War content is contained in the Administrative File series, including information about the 1861 "Baltimore Plot," Abraham Lincoln, the United States Secret Service, army engineer Henry L. Abbot, and Pinkerton operatives Kate Warne and Timothy Webster.

Included in the Administrative File is material related to a Pinkerton investigation of the company's main rival, the William J. Burns International Detective Agency. Pinkerton's criticized Burns's investigative methods, particularly his use of wiretaps, and the moral character of his operatives, some of whom had criminal records. For several years, Pinkerton's investigated the Burns agency and worked with a legal team that charged it with improper conduct. Records of the William J. Burns International Detective Agency investigation and subsequent hearings before the New York State Comptrollers office are included in the Administrative File series.