Caselaw Visualizations

Does the Flu “Infect” the Courts? Will COVID-19?

COVID-19 & Influenza’s Footprints in American Case Law

Throughout this series, we have analyzed the case law of diseases ranging from Yellow Fever, to HIV, to Smallpox. We’ve seen how certain epidemics seem to leave disproportionately large footprints in American case law while others are barely represented. Certainly, the personal health effects, business interruptions, and lasting economic consequences of the COVID-19 global pandemic have already shown themselves to be particularly prone to litigation:

Consumers continue to seek refunds for goods and services that have been disrupted by the COVID-19 pandemic, with colleges and universities being a particular target. Consumers also have targeted retailers for alleged price-gouging behavior. And, we continue to see new cases involving disputes over the applicability of business interruption and civil authority coverage to COVID-19 shutdowns.

Megan Mullins, Niall Paul, & Juseph Schaeffer of Spilman Thomas & Battle, PLLC, Unprecedented: COVID-19 Litigation Trends – Issue 6, JDSUPRA

Even if we focus specifically on class action suits, as of May 15, 2020, over 300 cases have already been filed across the United States, with the largest concentration in California.

Elise Haverman & Julianna Thomas McCabe of Carlton Fields, The Litigation Curve Does Not Flatten: COVID-19 Class Action Filings Approach 300, JDSUPRA, May 11

As states and municipalities in the US begin to relax stay-at-home orders and businesses begin to reopen, the following questions will likely lead to a further increase of COVID-19-related litigation:

Will wrongful death lawsuits expand beyond the meat-processing and cruise industries?

Will any college or university avoid a refund lawsuit?

Will employers face lawsuits over their use of the CARES Act funds?

How will force majeure cases be decided?

Are more fraud and whistleblower complaints on the horizon?

Megan Mullins, Niall Paul, & Juseph Schaeffer of Spilman Thomas & Battle, PLLC, Unprecedented: COVID-19 Litigation Trends – Issue 6, JDSUPRA (paraphrased)

Given the immense breadth and depth of these questions, it is very likely that the oncoming wave of litigation will last for years to come. For now, however, we can look at the legal and political footprint of influenza (the flu) as a backdrop against which the COVID-19 cases may be compared. In fact, just as COVID-19 has become a political talking point (see the analysis by FiveThirtyEight and their graph below), so too have flu epidemics.

Seth Masket, How Political Is The Coronavirus Pandemic Already?, FiveThirtyEight

For example, Michele Bachmann, a Republican member of Congress until 2015, attempted to find an ultimately innacurate connection between the swine flu epidemic of 2009 and the Democratic Party.

I find it interesting that it was back in the 1970s that the swine flu broke out then under another Democrat president, Jimmy Carter. And I’m not blaming [the 2009 swine flu epidemic] on President Obama, I just think it’s an interesting coincidence.

Michele Bachmann interview with Pajamas Media in April 27, 2009

PolitiFact addressed the factual inaccuracies in Bachmann’s statement as well as its logical gaps:

The president in 1976 was Gerald Ford — a Republican….So Bachmann is wrong about a Democrat being in charge during the 1976 outbreak and she fails to note the swine flu death in 1988. Hmmm. Two swine flu incidents during Republican administrations. By Bachmann’s logic, we should find that “interesting.” But we don’t. It’s ridiculous for her to suggest a partisan link with a deadly disease. That’s not just a mistake, that’s absurdly false.

Bill Adair, Michele Bachmann wrong that swine flu broke out under Carter, PolitiFact (emphasis added)

Going back to the case law footprint of the flu, we see the peaks and valleys of litigation roughly aligning with historical influenza epidemics in the United States (Major U.S. Epidemics), starting with 1889–1890 flu pandemic in which over 1,000,000 died worldwide.


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Specifically, we see visible increases after the 1889–1890 influenza pandemic, the 1918–1920 influenza pandemic, and the “Hong Kong” and “London” flu epidemics of 1968–1970 and 1972.

‘Influenza’ or the ‘Flu’?

Just for the sake of interest, I wanted to compare the use of “flu” and “influenza” to get a sense of how courts refer to the disease.

Etymologically, “[i]nfluenza earned its name from an Italian folk word that attributed colds, cough, and fever to the influence of the stars. Later the term evolved into influenza del freddo—’influence of the cold.‘” “The first influenza pandemic occurred around 1580, and the second in 1743, the latter spreading from Rome to England and introducing the word flu to the English.

For the grammar nerds, it’s notable that:

All of the great (read: notorious) illnesses seem to start with a definite article: the plague, the measles, the clap. Flu is no exception, appearing with the earliest English uses in the first half of the 19th century, about 100 years after the longer form entered English:

‘I have had a pretty fair share of the Flue.’

— Robert Southey, letter, 13 Aug. 1839.

‘Tis the (Flu) Season: The History of ‘Influenza’, Merriam-Webster

Concluding the Series

Over the course of these last three posts, we’ve covered some of the connections between communicable diseases, epidemics, and case law. Through geographical and diachronic analyses of the Case.Law dataset, we’ve seen how the public health, sociological, and economic dimensions of each disease outbreak affect its footprint on American case law and the legal system at large.

Life in the Time of Covid-19 is totally unprecedented.” So too may be COVID-19’s effect on the onslaught of lawsuits making their way through the American legal system. Only time will tell how this global crisis will affect judicial decisions and the dataset in the decades to come.


Word frequency for each state is determined by dividing the number of times the target word(s) appears over the total number of words in each state’s corpus (the total combined body of case law).

Word Frequency =(Word Count of the Target Word(s))/(Total Word Count)

Case frequency for each state is determined by dividing the number of cases that contain the target word(s) over the total number of cases in each state.

Case Frequency =(Cases that Contain the Target Word(s))/(Total Number of Cases)


Do you have any guesses or explanations about the findings shown above? Do you have any additional visualizations concerning epidemiology and law? Let me know @JoaoMarinotti on Twitter. This post is part of the Caselaw Visualizer Project. For a description of the dataset and the processes used to generate these visualizations, click here. The data was made available by the Harvard Law School Library’s Case Access Project (found at Case.Law). For information about me, click here.