D4.1.9-12: Arguments That Acknowledge Counterclaims and Weak Evidence

Overview

Lesson Procedure

75-80 minutes of class time across 5 phases.

1. Warm-Up10 minutes
2. Direct Instruction25-30 minutes
3. Guided Practice15 minutes
4. Independent Practice15 minutes
5. Closure10 minutes

1. Warm-Up10 minutes

   Warm-Up Prompt

   "A town upstream starts dumping waste into a river, and a town downstream reports more illness the next year. What would you need to know before you could say the first town caused the illness?"

   List answers: how many people got sick compared with the population, whether illness rose elsewhere too, whether anything else changed, how long germs survive in water, and how long the water takes to travel. Tell students these are exactly the questions the Supreme Court faced in 1906. Each one points to a possible evidentiary weakness, and a strong argument names the ones that apply instead of hiding them.

2. Direct Instruction25-30 minutes

   Part 1: The question. Chicago's sewage had been discharged into Lake Michigan; the canal turned the flow of the Chicago River so that the sewage went instead toward the Des Plaines and Illinois Rivers (Source 3). Missouri sued, arguing that the sewage reached the Mississippi and the water supply of St. Louis. The compelling question is "Was Chicago justified in reversing its river to carry its sewage away from Lake Michigan?" The dispute is a vehicle for the skill. Some terms: a bacillus (plural bacilli) is a rod-shaped bacterium; an intake is the point where a city draws its water; a diversion is water taken out of its natural course; and a special master is a person the Supreme Court appoints to take evidence and report findings.

   Source Information: who made each source, when, and whose interests it reports (from the sources and their source notes)

   Source	Maker	When	Interests and views it reports
   1: Missouri v. Illinois	Justice Holmes, for the Supreme Court	1906	Missouri's evidence, Illinois's (Chicago's) answers and the Court's judgment of both
   2: Hayes	Alfred Hayes, Jr., College of Law, Cornell University	1910	A secondhand summary of the case for general readers
   3: Encyclopedia	The New International Encyclopaedia	1905	The canal's purpose, size and cost
   4: Wisconsin v. Illinois	Chief Justice Taft, for the Supreme Court, reporting the special master's findings	1929	Chicago's earlier river problem and the six lake states' complaints
   5 and 6	Invented drafts and an invented scenario written for this page	Invented	Practice material; one draft in Source 5 is deliberately weak

   1We assume the now prevailing scientific explanation of typhoid fever to be correct. But when we go beyond that assumption everything is involved in doubt. The data upon which an increase in the deaths from typhoid fever in St. Louis is alleged are disputed. The elimination of other causes is denied. The experts differ as to the time and distance within which a stream would purify itself. No case of an epidemic caused by infection at so remote a source is brought forward, and the cases which are produced are controverted. The plaintiff obviously must be cautious upon this point, for if this suit should succeed many others would follow, and it not improbably would find itself a defendant to a bill by one or more of the States lower down upon the Mississippi. The distance which the sewage has to travel (357 miles) is not open to debate, but the time of transit to be inferred from experiments with floats is estimated at varying from eight to eighteen and a half days, with forty-eight hours more from intake to distribution, and when corrected by observations of bacteria is greatly prolonged by the defendants. The experiments of the defendants' experts lead them to the opinion that a typhoid bacillus could not survive the journey, while those on the other side maintain that it might live and keep its power for twenty-five days or more, and arrive at St. Louis. Upon the question at issue, whether the new discharge from Chicago hurts St. Louis, there is a categorical contradiction between the experts on the two sides.

   2The Chicago drainage canal was opened on January 17, 1900. The deaths from typhoid fever in St. Louis, before and after that date, are stated somewhat differently in different places. We give them mainly from the plaintiff's brief: 1890, 140; 1891, 165; 1892, 441; 1893, 215; 1894, 171; 1895, 106; 1896, 106; 1897, 125; 1898, 95; 1899, 131; 1900, 154; 1901, 181; 1902, 216; 1903, 281. It is argued for the defendant that the numbers for the later years have been enlarged by carrying over cases which in earlier years would have been put into a miscellaneous column (intermittent, remittent, typho-malaria, etc., etc.), but we assume that the increase is real. Nevertheless, comparing the last four years with the earlier ones, it is obvious that the ground for a specific inference is very narrow, if we stopped at this point. The plaintiff argues that the increase must be due to Chicago, since there is nothing corresponding to it in the watersheds of the Missouri or Mississippi. On the other hand, the defendant points out that there has been no such enhanced rate of typhoid on the banks of the Illinois as would have been found if the opening of the drainage canal were the true cause.

   1The state of Missouri brought suit against the state of Illinois to prevent the discharge of the sewage of Chicago by means of an artificial channel into the Des Plaines River, whence it entered the Illinois River and then the Mississippi. If this was a nuisance, by what law was it to be decided, that of Illinois or Missouri? The United States Supreme Court held that it could decide such controversies between states. Otherwise there would be no means of determining contests between states which in the absence of federation would be decided by war. But the court held that the rules applicable to private riparian owners did not necessarily apply between states and that the injury must be greater than a private injury to warrant relief. Missouri contended that the daily discharge of 1,500 tons of poisonous filth into this channel caused great injury to the public health in the state of Missouri since St. Louis and other cities took their water from the Mississippi River. Missouri showed that the number of deaths from typhoid fever had largely increased after the opening of the Chicago drainage canal. Missouri also showed by the presence in increased numbers in the Illinois River of the Bacillus coli communis, which it was agreed was an index as to the organic matter in the water, that the contamination was increased, but Illinois denied that injury to health had been caused, and so both sides conducted experiments to show the duration of life and capacity for travel of the Bacillus typhosus. It was conceded that typhus, cholera, dysentery, anthrax and tetanus are water-borne diseases and that it was practically impossible to discover the bacilli of typhoid in running water. It was proved by means of floats that the journey from Chicago to St. Louis, 375 miles, required from eight to eighteen and one half days. Then Missouri caused 107 barrels of the Bacillus prodigiosus to be put into the drainage canal near the starting point on November 6, On December 4, one of these bacilli was found at the St. Louis Intake Tower, and a few others later. The duration of life of this bacillus in sunlight in living water, being alleged to be about the same as that of the Bacillus typhosus, it was urged that the typhus bacillus in the sewage of Chicago could reach St. Louis. But Illinois contended that typhoid bacilli could live only for three or four days, and so the representatives of Illinois suspended in the Illinois River, sacs which water could penetrate. In these sacs were bacilli of typhoid and in three or four days there were no living typhoid bacilli in the sacs. Illinois therefore claimed that they had died, to which Missouri replied that the constant change of water made conditions different, that these bacilli may have been of less than normal strength, or that they may have escaped from the sacs. On all the evidence the court held that it was not sufficiently clear that a nuisance existed and the bill was dismissed without prejudice to the right of Missouri to commence over again if it believed that it had evidence strong enough to prove its case.

   1CHICAGO DRAINAGE CANAL. This canal was built to connect the west branch of the south fork of the Chicago River (q.v.) with the Des Plaines River, one of the head streams of the Illinois River, under such conditions that the water flows from Lake Michigan, through the Chicago River and the canal, into the Des Plaines River, thus reversing the direction of flow of the Chicago River. The object of the canal is to divert to the Illinois River the sewage of Chicago, which had been previously discharged into Lake Michigan. The engineering difficulties were peculiar, and aroused much professional and general interest. Work was begun on the canal on September 3, 1892, and it was formally opened on January 28, 1900. The canal proper begins on the west fork of the south branch of the Chicago River, at Robey Street, 5.8 miles from the lake, up to which point the Chicago River had to be dredged, and extends to Lockport, a distance of 28.05 miles, where the water action is controlled. [...] The width of the canal is 160 feet at the bottom and 162 feet at the top, through rock, and 110 to 202 feet at the bottom and 200 to 300 at the top, through earthy soil, the actual width in most of the distance being but 100 feet, this being sufficient for the flow of water at the rate of 300,000 cubic feet per minute. The depth is 36 feet, with a minimum depth of water of 22 feet. The cost of the canal up to the time of ‘opening’ was about $33,000,000. [...]

   1Before 1865, the Chicago River, being a sluggish stream in its lower reaches, had become so offensive because of receiving the sewage of the rapidly growing city, that for its immediate relief the municipal authorities and the canal commissioners agreed to pump water from the river in excess of the needs of navigation. By 1872 the summit level of the canal had been lowered, and it was hoped that this would result in a permanent flow of lake water through the South Branch of the Chicago River, sufficient to keep it in good condition, but the plan failed, and the canal again became grossly polluted.

   [...]

   2The diversion which has taken place through the Chicago Drainage Canal has been substantially equivalent to a diversion of about 8,500 cubic feet a second for a period of time sufficient to cause, and it has caused, the lowering of the mean levels of the Lakes and the connecting waterways, as follows: Lakes Michigan and Huron approximately 6 inches; Lakes Erie and Ontario approximately 5 inches; and of the connecting rivers, bays and harbors to the same extent respectively. A diversion of an additional 1,500 cubic feet per second, or a total diversion of 10,000 cubic feet a second would cause an additional lowering in Lakes Michigan and Huron of about one inch, and in Lakes Erie and Ontario a little less than one inch, with a corresponding additional lowering in the connecting waterways. The Master also finds that if the diversion at Chicago were ended, assuming that other diversions remained the same, the mean levels of the lakes and rivers affected by the Chicago drainage would be raised in the course of several years (about 5 years in the case of Lakes Michigan and Huron, and about one year in the case of Lakes Erie and Ontario) to the same extent as they had been lowered, respectively, by that diversion.

   Part 2: Model the moves. Work through the examples. Each one turns evidence into a precise, knowledgeable claim, or shows how to acknowledge a counterclaim or an evidentiary weakness inside the argument rather than leaving it for an opponent to find.

   • A precise claim from data (Source 1)

     Use the St. Louis typhoid deaths in Source 1, paragraph 2, to state a precise claim about the change after the canal opened.

     Result: Deaths averaged 1,695 ÷ 10 = 169.5 a year in 1890-1899 and 832 ÷ 4 = 208 a year in 1900-1903, an increase of about 23 percent. Precise claim: "Average yearly typhoid deaths in St. Louis rose by more than a fifth after 1900, by the plaintiff's own figures." The phrase "by the plaintiff's own figures" keeps the source's position in the claim.

   • Acknowledging an evidentiary weakness in the same data (Source 1)

     What weaknesses in these figures must an honest argument for Missouri admit?

     Result: First, the figures are counts, not rates: none of the sources gives the St. Louis population, so part of a rise could come from a growing city. Second, Illinois argued that later years "have been enlarged by carrying over cases" from a miscellaneous column. Third, the single year 1892 (441 deaths) is higher than any year after the canal opened. Holmes therefore calls "the ground for a specific inference" "very narrow" (paragraph 2).

   • A knowledgeable claim about the mechanism (Source 1)

     Missouri's case needed germs to survive the trip. State a claim that conveys this mechanism precisely.

     Result: The water took "from eight to eighteen and a half days" to arrive, with "forty-eight hours more" to distribution, so at most 18.5 + 2 = 20.5 days. Missouri's experts said the bacillus "might live and keep its power for twenty-five days or more", which is longer than the trip; Illinois's experts said it "could not survive the journey" (paragraph 1). Knowledgeable claim: "Whether Chicago harmed St. Louis turned on how long the typhoid bacillus survives in moving water, and on that question the experts gave 'a categorical contradiction'."

   • Handling a discrepancy between sources (Sources 1 and 2)

     Source 1 gives the distance as 357 miles; Source 2 gives 375. How should an argument handle this?

     Result: The two figures differ by 18 miles, possibly two digits switched in one source. An argument should use the figure from the opinion itself (Source 1), which Holmes calls "not open to debate", and mention that a later summary differs. The discrepancy is also a warning about Source 2 in general: Hayes's secondhand summary may contain other slips.

   • Acknowledging and answering a counterclaim (Source 4)

     An argument says Chicago was justified. What is the strongest counterclaim, and how can the argument answer it?

     Result: Counterclaim: the diversion harmed other states, lowering "Lakes Michigan and Huron approximately 6 inches" (Source 4, paragraph 2). Answer: the same source shows Chicago faced a serious problem, since its river had become "grossly polluted" even after the 1872 plan (paragraph 1), and the master also found the levels would recover in about 5 years if the diversion ended. The answer concedes the harm and argues it could be limited, which is stronger than denying it.

3. Guided Practice15 minutes

   Groups of three read Source 5, three invented draft arguments; one is deliberately weak. For each draft, groups mark the precise claims, the sources used, the counterclaim acknowledged and the evidentiary weakness named, and then list what is missing. They study the typhoid chart (Diagram 1) while they work.

   1These three drafts were written for this page by invented students who read Sources 1-4. One of them is deliberately weak, for practice. None is a model to copy.

   2Rosa: "Chicago was justified. The canal sent sewage away from Lake Michigan, where it had been discharged before (Source 3), and the Supreme Court ruled that Missouri had not proved its case (Source 1). A counterclaim is that the canal later lowered Lakes Michigan and Huron by about 6 inches (Source 4, paragraph 2). That cost was real, but it was not known in 1900."

   3Sam: "Chicago poisoned St. Louis. Hayes says typhoid deaths 'largely increased' after the canal opened (Source 2), and the numbers prove it."

   4Tara: "Chicago's decision was defensible for Chicago but shifted costs to others. The river had been 'grossly polluted' even after the 1872 attempt to fix it (Source 4, paragraph 1), so Chicago faced a real problem. But Missouri's experts described harm downstream (Source 1), and the special master in the lake states' case found that the lakes were lowered (Source 4). The St. Louis death figures are disputed, so the harm to St. Louis is the weakest part of the case against Chicago."

   Teacher key (discussion points). Rosa uses three sources and acknowledges a counterclaim, but her last sentence ("it was not known in 1900") is an assertion with no source behind it, which is itself an evidentiary weakness she should flag or support. Sam's draft is the deliberately weak one: it rests on a secondhand summary, ignores that the figures are disputed, never mentions Illinois's evidence, and says the numbers "prove" what the Court found unproved. Tara's draft is the most complete: its claim is limited ("defensible for Chicago but shifted costs to others"), it draws on several sources, and it names its own weakest point. Groups should still ask what "shifted costs" means in numbers.

4. Independent Practice15 minutes

   Each student writes an argument of two or three paragraphs answering the compelling question. Requirements: a precise and knowledgeable thesis claim; evidence from at least three of Sources 1-4, cited by paragraph; at least one calculation or exact figure; the strongest counterclaim, answered with evidence; and at least two named evidentiary weaknesses, with a sentence on how each limits the conclusion.

5. Closure10 minutes

   Exit ticket: "Name the single weakest piece of evidence for your own side, and explain why you still hold your claim."

   Teacher note on the sources: Sources 1 and 4 are court opinions; they report the parties' evidence and the Court's judgment, not a scientific verdict. The death figures in Source 1 are counts of deaths, not rates: no source on this page gives the population of St. Louis, so students should not describe them as a death rate. They come mainly from the plaintiff's brief, and Holmes says they are "stated somewhat differently in different places". The page keeps three discrepancies exactly as the sources print them, for students to find: the opening date (January 17, 1900 in Source 1, January 28, 1900 in Source 3), the distance (357 miles in Source 1, 375 in Source 2) and the disease (Source 2 twice writes typhus, a different disease, where the case was about typhoid). They are errors or disagreements in the sources, not on the page. The question asks about a historical decision; both sides can be argued well.

   Quiz passage. Questions 11-14, 19 and 20 use Source 6, an invented scenario.

   1This scenario is invented for this page. The places, the people and all the numbers are invented.

   2In the invented county of Harlan, a paper mill opened a new discharge pipe into Mill Creek in May. That summer, people found dead fish along a 4-mile stretch downstream. A county board must decide whether to order the mill to close the pipe.

   3Source 6A, county fish counts (dead fish found in July surveys): 2021, 30; 2022, 45; 2023, 38; 2024 (after the pipe opened), 120.

   4Source 6B, the creek's water temperature in July 2024 was the highest in the county's records, which began in 2010. Warm water holds less oxygen.

   5Source 6C, a lab hired by the mill: water samples taken 100 yards below the pipe in August met the state's standards for the chemicals tested.

   6Source 6D, a biologist hired by a fishing club: dead fish were found only below the pipe, none above it. The mill's samples were taken after the fish had died, and they did not test for oxygen.

Differentiation Strategies

Assessment Guidance

1. Question 1 of 20 · Multiple Choice

   Holmes writes, "The data upon which an increase in the deaths from typhoid fever in St. Louis is alleged are disputed. The elimination of other causes is denied" (Source 1, paragraph 1). Which evidentiary weakness does the second sentence name?

   AThe death counts had been lost before the trial BOther possible causes had not been ruled out CThe experts all agreed with Missouri's case DThe distance to St. Louis was never measured

2. Question 2 of 20 · Multiple Choice

   Holmes notes that "No case of an epidemic caused by infection at so remote a source is brought forward" (Source 1, paragraph 1). What does this sentence tell a reader about Missouri's evidence?

   AMissouri gave no past example of disease carried so far BMissouri proved that every single epidemic starts far away CMissouri showed that Chicago had no typhoid at all DMissouri's experts found typhoid bacilli at St. Louis

3. Question 3 of 20 · Multiple Choice

   Holmes says Missouri "must be cautious", because if it won, "many others would follow" (Source 1, paragraph 1). What risk is he pointing to?

   AChicago would close the canal at once BIllinois would refuse to pay for filtration CThe Court would lose its power over states DMissouri could be sued by downstream states

4. Question 4 of 20 · Multiple Choice

   Hayes writes that without the Court, contests between states "in the absence of federation would be decided by war" (Source 2). What point is he making?

   AStates had often gone to war over rivers BThe Court gives states a peaceful remedy CMissouri threatened Illinois with war DFederal law forbids states to use rivers

5. Question 5 of 20 · Multiple Choice

   Hayes says it "was practically impossible to discover the bacilli of typhoid in running water" (Source 2). Why is this an evidentiary weakness for Missouri?

   AIt meant that the river held no germs of any kind BIt meant the trip took far less than a day CIt meant direct proof of the germ was missing DIt meant Illinois had hidden the evidence

6. Question 6 of 20 · Multiple Choice

   Hayes ends: the bill "was dismissed without prejudice to the right of Missouri to commence over again if it believed that it had evidence strong enough" (Source 2). Which statement about the outcome is the most precise?

   AThe Court ruled that Chicago's sewage was harmless BThe Court found that Missouri had won the case CThe Court said its evidence fell short, for now DThe Court banned all future suits about rivers

7. Question 7 of 20 · Multiple Choice

   Which claim about the canal's cost does Source 3 support most precisely?

   AIt cost about $33 million up to its opening BIt cost exactly $33 million in all, by 1929 CIt cost more than any other U.S. project DIt was paid for by the federal government

8. Question 8 of 20 · Multiple Choice

   An argument that Chicago was justified says the city tried smaller fixes before it built the drainage canal. Which detail in Source 4, paragraph 1, about what was done "for its immediate relief" before 1865, is evidence for that claim?

   AIt built the main drainage canal at once BIt pumped extra water from the river CIt moved the city's water intake DIt sued the state of Missouri

9. Question 9 of 20 · Multiple Choice

   Source 4 reports that an additional diversion of 1,500 cubic feet per second would lower Lakes Michigan and Huron by "about one inch" (paragraph 2). Which claim does this support precisely?

   AAny diversion at all would empty the lakes BThe lakes would rise if diversion grew CLake levels did not depend on the Chicago canal DLarger diversions would lower lakes further

10. Question 10 of 20 · Multiple Choice

    Which thesis is both precise and knowledgeable?

    AChicago was completely right to build the canal, and anyone who disagrees is wrong BThe canal was a huge engineering project that changed a great many things CChicago harmed every person who lived along any river or lake in the region DChicago moved its sewage risk downstream, where the harm to St. Louis was disputed

11. Question 11 of 20 · Multiple Choice

    An argument for closing the pipe needs a precise claim about Source 6A. Which claim compares the 2024 count with the 2021-2023 average accurately? The 2024 count was...

    AAbout 1.1 times the average BAbout 2.7 times the average CAbout 3.2 times the average DAbout 4 times the average

12. Question 12 of 20 · Multiple Choice

    Which counterclaim to "the pipe killed the fish" does Source 6B support?

    ARecord heat may have lowered the oxygen BThe mill closed the new pipe before July CThe fish died far above the new pipe DThe lab found harmful chemicals in it

13. Question 13 of 20 · Multiple Choice

    What is an evidentiary weakness of Source 6C, the mill's lab results?

    AIt tested water far upstream of the mill BIt was paid for by the county fish board CIt came after the kill and skipped oxygen DIt found the creek water failed standards

14. Question 14 of 20 · Multiple Choice

    Which evidence best answers the counterclaim that the heat, not the pipe, killed the fish?

    AThe 2023 count of 38 dead fish BDead fish only below the pipe CThe mill lab's chemical results DThe start of records in 2010

15. Question 15 of 20 · Short Answer

    Write a precise and knowledgeable thesis on the compelling question, "Was Chicago justified in reversing its river to carry its sewage away from Lake Michigan?" Support it with evidence from at least three of Sources 1-4.

    Show model answer

16. Question 16 of 20 · Short Answer

    State the strongest counterclaim to your thesis in Question 15, and answer it with evidence.

    Show model answer

17. Question 17 of 20 · Short Answer

    Name two evidentiary weaknesses in the record of Missouri v. Illinois, and explain how each limits any conclusion about whether Chicago harmed St. Louis.

    Show model answer

18. Question 18 of 20 · Short Answer

    Explain how using sources that represent different interests (St. Louis, Chicago and the Great Lakes states) makes an argument about the canal stronger. Give one example.

    Show model answer

19. Question 19 of 20 · Short Answer

    Use Source 6 to write a short argument for the Harlan county board: should it order the mill to close the pipe? Include a precise claim, the strongest counterclaim, and one evidentiary weakness.

    Show model answer

20. Question 20 of 20 · Short Answer

    Both the mill's lab (6C) and the fishing club's biologist (6D) were hired by an interested party. Name one evidentiary weakness of each, and explain how a fair argument should use them.

    Show model answer

These standards connect to D4.1.9-12: prerequisites to review first, parallel standards at the same level, and next steps that build on it.

Standard text: National Council for the Social Studies (NCSS), The College, Career, and Civic Life (C3) Framework for Social Studies State Standards: Guidance for Enhancing the Rigor of K-12 Civics, Economics, Geography, and History (Silver Spring, MD: NCSS, 2013). NCSS was not involved in the production of this lesson and does not endorse it.