How to Detect and Demonstrate Plagiarism
By Susan Mosher Stuard and William J. Cronon
After one discovers an instance of plagiarism, the next task is generally to prove conclusively that it has in fact occurred. The classic tools for providing such proof are side-by-side parallel texts, in which passages from the original document are presented next to passages from the text that plagiarizes them, usually in adjacent vertical columns.
The number, length, and complexity of examples depends on the extent of the plagiarism, but also on the context in which the parallel texts will be presented. At one extreme would be evidence presented in a legal proceeding or a formal disciplinary hearing; at the other would be the very limited space typically permitted in a standard book review, where even the typography of vertical columns will not usually be possible.
In general, the greater the number and length of the parallel examples, the more persuasive will be the demonstration that plagiarism has in fact occurred. But whether the side-by-side texts consist of a two or three quoted sentences in a book review or run to dozens of pages in a legal brief, the underlying principle remains the same: one proves plagiarism by offering as evidence parallel texts that resemble each other so unmistakably that no disinterested reader could believe they occurred by accident.
Demonstrating Plagiarism with Parallel Texts
To identify plagiarism pay attention to expropriation of another author’s text and presentation of it as one’s own. This includes more than simply expropriating the exact wording of another author without attribution. Another person’s distinctive voice and significant research, findings, hypotheses, theories, rhetorical strategies, or interpretations may not be borrowed, even if “disguised in newly crafted sentences or referenced to a borrowed work in an early note with extensive further use without any attribution.” Pay attention to a plagiarist’s attempts to track another’s text. Borrowing another’s distinctive voice may include following another’s interpretation and along the way appropriating concepts, data, and notes as well as distinctive vocabulary, syntax, and specialized word constructions.
The three following examples illustrate three different variants of plagiarism: 1) expropriation of another author’s text; 2) paraphrasing another author’s text without attribution; and 3) borrowing from a series of different places in another’s work in order to construct a paragraph. (Please note that this is a teaching device. The plagiarism is a fiction constructed for demonstration purposes only, with the author’s full permission to do so.)
In Example 1 look for the expropriation of another author’s text in the precise order of the original. There are a few omissions and some sentences change a word or two, but the two paragraphs are substantially the same, including the plagiarized footnotes. The plagiarizer found it necessary to check the bibliography for the full reference to Benjamin F. Goldstein’s book cited in footnote 2. Please note that plagiarism occurs here despite Big Shoulders’ different interpretation of one subject of the paragraph, Ira Munn. Indeed the next (putative) paragraph of Big Shoulders applauds Ira Munn (inaccurately) as the father of the commodities futures contract in Chicago.
Excerpt from Anonymous, Big Shoulders: Chicago in Picture and Prose (Gary, IN: Trade Books, Inc., 2003), i-vi, 1-307.
Big Shoulders, p. 86, facing fig. 29, captioned “Portrait of Ira Munn, branded a monopolist”
In 1877, the United States Supreme Court issued its famous ruling in Munn v. Illinois, establishing the principle that grain elevators and other such facilities were “clothed with a public interest” and could not escape state regulation. Ira Munn, Chicago’s leading elevator operator, would henceforth be associated with this ruling that enabled state governments to regulate public good and private interests in economic matters. Ira Munn would be forever branded as a monopolist. As one scholar stated in 1928, Munn v. Illinois “was epoch making in its consequence and … has remained an active force in American history to the present day.” Chicago’s relationship to the new “public interest” as articulated in Munn may only be called ambivalent.
1. The best recent surveys of the issues involved are Edmund W. Kitch and Clara Ann Bowler, “The Facts of Munn v. Illinois,” in Philip B. Kurland and Gerhard Casper, eds. 1978: The Supreme Court Review (1979), 313–43; and Harry N. Scheiber, “The Road to Munn: Eminent Domain and the Concept of Public Purpose in the State Courts,” Perspectives in American History 7 (1971): 327–402.
2. Benjamin F. Goldstein, Marketing a Farmer’s Problem (New York: Macmillan, 1928) p. 96.
Excerpt from William Cronon, Nature’s Metropolis: Chicago and the Great West (New York and London: W. W. Norton, 1991), 142.
Finally, in 1877, the U. S. Supreme Court issued its famous ruling in Munn v. Illinois, establishing forever the principle that grain elevators and other such facilities were “clothed with a public interest” and could not escape state regulation. The name of Ira Munn, Chicago’s leading elevator operator, would henceforth be associated with a legal ruling that enabled state governments to regulate the boundary between private interest and public good in economic matters. In making their decision, the justices were clearly impressed by what they saw as the harmful public consequences of monopoly power at Chicago’s grain elevators, but the case had much wider ramifications. As one early student of the subject remarked in 1928, Munn v. Illinois “was epoch making in its consequences,” and “through it the Granger Movement has remained an active force in American history to the present day.”
Chicago’s relationship to the new “public interest” as articulated in Munn can only be called ambivalent.
1. (in text, note 186 for Chapter 3, pp. 422–23) Goldstein, Marketing, 64–69, contains a useful summary of Munn, but the literature on this case is enormous. The best recent surveys of the issues involved are Edmund W. Kitch and Clara Ann Bowler, “The Facts of Munn v. Illinois,” in Philip B. Kurland and Gerhand Casper, ed., 1978: The Supreme Court Review (1979), 313–43; and Harry N. Scheiber, “The Road to Munn: Eminent Domain and the Concept of Public Purpose in the State Courts,” Perspectives in American History 7 (1971): 327–402.
2. (in text, note 187 for Chapter 3, p. 423) Goldstein, Marketing, p. 96.
In Example 2 the plagiarizer paraphrased a text from Nature’s Metropolis and shortened the paragraph considerably. Phrases such as “unique,” Gateway City to the West, and Mythic City were apparently too attractive to resist. Note the change of voice. In a postscript the author of Nature’s Metropolis explains his motives for undertaking his study of Chicago by switching to the “I” voice. Big Shoulders employs the regal “we” voice, but this in no way obscures the underlying parallelisms.
Excerpt from Big Shoulders, p. 299
It is possible to look at Chicago in two different ways. On the one hand Chicago has a very particular history during a remarkable era. Chicago really deserves that often-used phrase, “a unique place,” and it played a central role in building the landscapes and markets of North America, as we know them today. But Chicago may also stand as the quintessential U.S. city and marketplace. Even New York City is not dramatically different in the role it has played in our history. And Chicago, Gateway City to the West, has characteristics that apply just as easily to other cities that represent our westward expansion. How a city’s life affects the countryside around it is a question for all cities, great and small. In its most encompassing dimension this is a study of The Mythic City as a place distinct from, yet essential to, that other key to our mythic human landscape, The Country.
Excerpt from Nature’s Metropolis, pp. 383–84
Throughout this book, I have written of Chicago in two different ways. Much of the time, I have described the very particular history of an extraordinary city during a remarkable time in its history. Viewed in this context, Chicago really does deserve that overused word “unique,” and really did play a pioneering role in shaping the markets and landscapes of North America as we know them today. But at other times I have allowed Chicago to stand as a representative for cities and markets more generally, so that much of what I have said about it would also hold true for other places. Similar things could be said even more dramatically about New York City. Many of Chicago’s characteristics apply just as easily to the other gateway cities I have described, and one could write similar books for each of them as well. And the most general question of all—how a city’s life and markets connect to the countryside around it—can be asked of every urban place that has ever existed, no matter how large or small. I embarked on this book because I was and am troubled that we so rarely ask just that question. And so this book about Chicago has also been a book about The City, in its largest, most mythic sense as a place somehow separate from that other key human landscape, The Country.
Example 3 represents a greater challenge to detection because it borrows text and an illustration that appear in five different places. The author of Big Shoulders was tempted to include the dramatic photo of an enormous logjam that he found between pages 168 and 169 in Nature’s Metropolis. He appropriated the illustration, its caption, and its credit to the State Historical Society of Wisconsin with no attribution or permission from the society (a violation of copyright). To justify this borrowing, Big Shoulders cobbled together a paragraph that drew sentences from a longer discussion of lumbering found in the original text. The topic is remote from Big Shoulders’ subject, the city of Chicago itself, whereas in Nature’s Metropolis it advances the book’s key thesis about the interaction of the city with the surrounding countryside.
Excerpt from Big Shoulders, p. 221, and facing caption for fig. 186
Breaking a jam. Sometimes a logjam could be broken using teams of horses to pull logs on to shore, or by dynamiting strategic logs, but workers often ended up breaking the jam by working away at the face of the roaring mass. The faint of heart need not apply. Courtesy State Historical Society of Wisconsin. ...
The down-and-out and the underemployed found work in the lumber business. Drummers were men of little means, even on occasion, failed lumber dealers, who worked on commission to obtain orders for their bosses among powerful Chicago lumber wholesalers. The actual journey of white pine from site to sawmill to Chicago’s vast lumberyards traced an annual cycle following the flood and ebb in local lakes and rivers. Logging was winter work balancing the seasonal nature of agricultural work in the northern U.S. The coming of warm weather signaled a time for crews of men (many of them out of work between mud season and the beginning of floods) to head downstream in order to start the logs on their journey. Logs might jam in a shallow or narrow place in the river, causing a nightmarish tangle known as a logjam. Logs could pile up for miles, overflowing rivers, destroying structures on shore, and taking men’s lives. The 1869 jam at Chippewa Falls, Wisconsin, was fifteen miles from front to back and stood thirty feet high. In the 1888 pileup on the Menominee River, a billion board feet of timber got stuck at great cost to lives.
1. See Frederick Merk, Economic History of Wisconsin during the Civil War Decade (1916; reprint 1971).
Excerpt from William Cronon, Nature’s Metropolis
Illustration caption between pp. 168–69
Breaking a jam. A logjam could be broken by using teams of horses to pull logs onto the shore, or even by dynamiting strategic logs in the hope of loosening the rest. But in the end, workers often had to go out onto the face and hack away by hand at the roaring mass. It was not a job for the faint of heart. Courtesy State Historical Society of Wisconsin. ...
p. 185: Drummers were men of little means, sometimes failed lumber dealers themselves, who worked on commission to obtain orders on behalf of Chicago lumber wholesalers.
p. 155: Indeed, the entire journey of white pine from forest to sawmill to city yard traced a clear annual cycle whose rhythms followed the seasonal movements of water. Logging was a winter activity, roughly counterpointing the agricultural year.
p. 157, paragraph 1: In good years, on the other hand, the coming of warm weather signaled the time when crews of men (many of whom had been without work for several weeks between the beginning of mud season and the arrival of the floods) headed down the streams to shepherd the logs on their journey.
p. 157, paragraph 2: The worst fear of the men was that a few logs might become caught at a shallow or narrow place in the river, causing thousands of others to back up behind them in the nightmarish tangle known as a logjam. Logs might pile up for miles behind such an obstruction, overflowing the river’s banks, destroying structures on shore, and wreaking havoc with the forward movement of the drive. … The 1869 jam at Chippewa Falls, Wisconsin, for instance, backed up fifteen miles from its front, stood thirty feet high in some places, and reportedly contained something like 150 million board feet of timber. More impressive still was the 1888 pileup on the Menominee River, where over half a billion board feet of timber got stuck.
1. (in text, note 23 for Chapter 4, pp. 425–26) The literature on logging and the Great Lakes lumber industry in general is so enormous as to defy easy summary. Among the best academic surveys of Great Lakes logging and life in the lumber camps are Frederick Merk, Economic History of Wisconsin during the Civil War Decade (1916; reprint, 1971); [there follow 28 lines of other references].
2. (in text, note 35 for Chapter 4, p. 426) Rector, Log Transportation, 257; Fries, Empire in Pine, 45.
 American Historical Association Statement on Standards of Professional Conduct (Washington, D.C.: American Historical Association, 2003) p. 10-11. This introduction paraphrases paragraphs three and four of the “Statement on Plagiarism,” pp. 10-11, with a few additions.
 Ibid., p. 11.