by Kenneth R. Brown*

Contact tracing emerged during the beginning of the COVID-19 pandemic as an important tool to reduce the spread of COVID-19. The use of cell phone applications provides a method to effectively trace potential exposures since most individuals carry cell phones that can easily gather the necessary data. The federal government has thus far failed to introduce its own regulations regarding the large volume of data that can be collected during contact tracing efforts or attempt to help coordinate the regulations of the individual states to ensure consistency; paving the way for a patchwork system of rules to govern, as each state is left to formulate its own method to protect the health and privacy of its residents. However, due to the volume of interstate travel and difficulty of restricting application usage based on state borders, states must be careful not to run afoul of the so-called “Dormant Commerce Clause” of the United States Constitution. In this Contribution, Kenneth Brown (’22) argues that it is possible for a state to effectively regulate con-tact tracing applications without violating the Constitution.

The COVID-19 pandemic has had a profound impact on the lives of individuals around in the world. As of February 2022, COVID-19 has infected at least 75 million people in the United States alone, killing more than 915,000 of them.1 The federal and state governments have taken extensive measures to mitigate the spread of the virus and prevent the failure of patchwork systems of hospitals due to excess patients. These measures include contact tracing, travel restrictions, stay at home orders, mask mandates, vaccine mandates, and forced closure of non-essential businesses.

Contact tracing is one of the more effective strategies to identify clusters of COVID-19 transmission and limit further spread.2 The use of mobile phone applications allows for the easy collection of data related to demographics, COVID status, and geolocation that furthers contact tracing efforts. Due to the limited nature of federal police powers under the U.S. Constitution, contact tracing solutions are managed at the state level. Absent federal oversight and cooperation among sovereign equals, these efforts vary in methodology, efficacy, and scope of data sharing. Because U.S. citizens frequently travel between states, states may need to monitor the movements of their residents while they are outside of the state in order to effectively implement contact tracing solutions and limit the spread of COVID-19 within their state. To protect the privacy of what could be considered sensitive data, states may also need to restrict the information that non-resident contact tracing entities may share regarding data collected within the state’s borders or from its residents while they are outside of the state.

State legislation that reaches extraterritorially into its fellow sovereign states would be subject to restrictions under the Dormant Commerce Clause of the Constitution. In order to be constitutionally valid, such legislation would need to pass a balancing test considering the follow factors: (1) whether it discriminates against interstate commerce, (2) directly regulates commerce outside of its territory, or (3) burdens interstate commerce in a manner that clearly exceeds the benefits to the state’s legitimate interest. This Contribution argues that state legislation authorizing the collection and use of data sourced from contact tracing applications would be a valid exercise of state police powers under the Dormant Commerce Clause.


The Commerce Clause of the Constitution grants Congress the power to “regulate Commerce with foreign Nations, and among the several states, and with the Indian Tribes.”3 The Constitution’s Supremacy Clause makes this grant of power supreme and binds each state to enforce it, notwithstanding any state law to the contrary.4 As such, the Supreme Court has noted that “the Commerce Clause is a power-allocating provision” that gives Congress “pre-emptive authority over the regulation of interstate commerce.”5

The Framers wrote the Commerce Clause to “avoid the tendencies toward economic Balkanization that had plagued relations among the Colonies and later among the states under the Articles of Confederation.”6 In accord with this understanding, the Supreme Court has long held that the Commerce Clause has an implied prohibitive effect on state legislation that unduly burdens interstate commerce, termed by the Court the “dormant Commerce Clause”.7 This prohibitive effect restricts state action “even when Congress has failed to legislate on the subject.”8 However, absent contradicting federal legislation, the states retain some authority to regulate matters that affect interstate commerce, as long as it is of “legitimate local concern.”9

A state’s authority to enact legislation that impacts interstate commerce does not extend to the enactment of legislation with a discriminatory purpose; such legislation is “virtually per se” invalid.10 The Supreme Court has applied this rule to invalidate legislation that directly discriminates against interstate commerce or that effectively favor in-state activity over out-of-state activity.11 Historically, legislation that has no reason, other than its interstate status, to treat interstate commerce differently than intrastate commerce is subjected to a form of strict scrutiny: the state must justify the local benefits from the statute and demonstrate that there were no nondiscriminatory alternatives that could adequately preserve those benefits.12 If the legislation is not so narrowly tailored, it must be struck down.13

While state legislation may impact interstate commerce, the Commerce Clause does not allow a state to directly regulate commerce that occurs outside of its territory.14 This is true even if the effect of the legislation was initially triggered by in-state activity.15 Even if commerce has effects within the state, “[t]he Commerce Clause . . . precludes the application of a state statute to commerce that takes place wholly outside of the state’s borders.”16 This restriction applies when legislation has the “practical effect” of extraterritorial reach.17 Generally, the Supreme Court has used the Commerce Clause to invalidate legislation with extraterritorial effect in cases where states have attempted to set price controls18 or restrict the actions of companies that have a potentially tenuous connection to the state.19

Nondiscriminatory state legislation that incidentally effects interstate commerce and has not been preempted by Congress is valid if it is fairly applied to activity with a “substantial nexus” to the state and related to the services provided by the state.20 The legislation will be upheld if the burden placed on interstate commerce is not “clearly excessive in relation to the putative local benefits.”21

The weight afforded to a state’s interest may depend upon its character. For instance, the Supreme Court has stated that the balancing of the burden on interstate commerce against a state’s safety interest “naturally” differs from that of an economic interest.22 The Supreme Court has historically provided more deference under the Commerce Clause to state regulations that concern health and safety.23 In Railway Express Agency, Inc., the Supreme Court upheld a New York City ordinance that banned the use of vehicles for the primary purpose of advertising in order to prevent fellow drivers and nearby pedestrians from becoming distracted, despite the burden this would place on interstate trucking commerce.24 Later, in United Haulers Association, the Supreme Court upheld county ordinances that required all solid waste generated by their citizens be delivered to a state-created public benefit corporation.25 The Court reasoned that states were “vested with the responsibility of protecting the health, safety, and welfare of its citizens,” and that the local government was allowed to favor the use of an in-state public entity in order to pursue its environmental goals.26 The evidence of the benefit to the state must be conclusive.27 Legislation that only marginally furthers such purposes may be invalid if it substantially affects interstate commerce.28


Contact Tracing applications collect sensitive consumer information such as their location history and COVID-19 status in order to effectively combat the spread of the virus. State legislation regulating how applications may collect, store, and sell this information would serve both privacy and health interests, which have both been recognized by the Court as legitimate substantial interests that states may protect by enacting legislation under their police powers.29 While provisions governing the use of contact tracing application data would not directly address health and safety, it does so indirectly in two ways. The first, and most important, is that legislation may require the application to send the data to the state so that it can reach out to individuals who have had potential contacts with someone who has tested positive COVID-19 or publish information that would allow individuals to make that determination for themselves. The second is that restrictions on the usage of personal data collected from the application may increase user confidence that their information will be protected and reduce hesitancy to use the application, encouraging wider use of contact tracing applications by the general public.

Since the federal government has not enacted legislation that would conflict with, or preempt, state legislation purporting to regulate the collection, processing, and transfer of geolocation data by contact tracing applications, such state legislation could be valid under the Dormant Commerce Clause. Even if the legislation were to have an effect on interstate commerce, such as imposing burdensome extra costs onto nonresident application owners or restricting lucrative sources of income, it would remain constitutionally valid as long as it did not discriminate against or directly regulate interstate commerce and the state’s benefits from the legislation would not be clearly exceeded by the burden on interstate commerce.

To avoid discrimination, the legislation’s provisions should not explicitly address interstate commerce by taking into account the residency status of the contact tracing application’s corporate owner(s). The Supreme Court has held that legislation with provisions explicitly charging increased fees or adding additional burdens to out-of-state businesses discriminate against interstate commerce in violation of the Commerce Clause.30 The legislation should also not have provisions that would favor in-state owners, such as a mandate to partner with local businesses or to use local products or employees that reside within the state. However, even if some provisions potentially place additional burdens on out-of-state businesses, they might survive the strict scrutiny analysis if there were no reasonable alternative methods to satisfy the state’s substantial interests in protecting the health and privacy of its citizens. An example would be requirements to interact with the state itself, or where the state is acting as a market participant, in order to ensure that it receives sufficient data to effectively trace potential contacts with individuals that have tested positive for COVID-19.  This would be a valid indirect discrimination as long as any alternative would be more costly or practically impossible.31

To effectively regulate contact tracing applications, any state legislation must, at least on occasion, affect conduct occurring outside of the state’s borders or performed by non-residents within the state, as the state cannot legally stop the flow of individuals or commerce coming into and out of the state and COVID-19 does not recognize borders. The legislation must be carefully crafted so that it does not affect conduct that is occurring completely outside of its borders, such as interactions between its residents and contact tracing applications owned by non-resident companies while the resident is outside of the state. Even if the contact tracing application is advertised within the state and has an effect within the state, legislation affecting such transactions would violate the Commerce Clause.32

The language should also not conflict with the laws of other states where it reaches in a manner which essentially requires out-of-state contact tracing application owners to choose between the laws of those states or conduct business at the regulating state’s direction.33 To avoid running afoul of these strictures, legislation could be crafted in a manner that doesn’t conflict with the laws of its fellow states. This would avoid creating “just the kind of competing and interlocking local economic regulation that the Commerce Clause was meant to preclude.”34 A legislature could avoid this problem by studying the laws of other states prior to crafting the legislation or, ideally, working with other states to create uniform provisions that would make it easier for contact tracing applications to work across state lines. Any provisions that directly address the management of resident data collected by out-of-state actors could be narrowly tailored to apply only to that data collected within the state.

Limiting the spread of COVID-19 and restricting the sale or mismanagement of their residents’ personal data implicates the state’s interest in protecting the health and privacy of its citizens. If the legislation is crafted to be non-discriminatory, except where necessary, and if it has a circumscribed extraterritorial effect, then the burden that it places on interstate commerce should be minor and would have only incidental compliance costs. Even if there were substantial costs imposed on interstate commerce by the legislation, it would still need to clearly exceed the benefits to be a violation of the Dormant Commerce Clause. Given the high level of deference given to state laws intended to protect health and safety, it is an extraordinarily high bar to clear. As the Supreme Court stated in Compagnie Francaise de Navigation a Vapeur v. Board of Health of State of Louisiana, “the power of the states to enact and enforce quarantine laws for the safety and the protection of the health of their inhabitants . . . is beyond question” even if it “affects interstate or foreign commerce.”35


State legislation that provides for and governs contact tracing applications and their associated use of private, sensitive user data is a valid use of a state’s police power and supports its substantial interest in protecting the health and privacy of its residents. Such legislation, if properly constructed, should be considered valid under the Dormant Commerce Clause because it would not discriminate against or directly regulate interstate commerce.  Further, the state’s benefits from the legislation would equal or exceed the burden on interstate commerce. To find otherwise would risk hampering important efforts to limit the spread of COVID-19 and manage a pandemic that has already exacted a significant toll on the lives of people throughout the United States and the world.

* Kenneth Brown is a J.D. Candidate (2022) at New York University School of Law. This piece is a commentary on the problem produced for the 2021 National Telecommunications and Technology Moot Court Competition hosted by The Catholic University of America Columbus School of Law, together with the Federal Communications Bar Association. The question presented was whether the dormant Commerce Clause allows a state to place disclosure requirements on and restrict the sale of consumer information collected by contact tracing applications operated by a company that resides in a different state. The views expressed in this article do not necessarily represent the views of the author.

1. Ctrs. for Disease Control and Prevention, (last visited Feb. 15, 2022).

2. Case Investigation and Contact Tracing: Part of a Multipronged Approach to Fight the COVID-19 Pandemic, Ctrs. for Disease Control and Prevention, (last updated December 3, 2020).

3. U.S. Const. art. I, § 8, cl. 3.

4. U.S. Const. art. VI, cl. 2.

5. Dennis v. Higgins, 498 U.S. 439, 447 (1991).

6. Okla. Tax Comm’n v. Jefferson Lines, 514 U.S. 175, 180 (1995) (quoting Wardair Canada Inc. v. Florida Dept. of Revenue, 477 U.S. 1, 7 (1986)).

7. See, e.g., Dep’t of Revenue v. Ass’n of Wash. Stevedoring Cos., 435 U.S. 734, 749 (1978) (stating that it is the combination of the Supremacy Clause and the Supreme Court’s prior decisions which creates the prohibitive effect); Dennis, 498 U.S. at 446 (“[T]he Court long has recognized that it also limits the power of the states to erect barriers against interstate trade.” (quoting Lewis v. BT Investment Managers, Inc., 447 U.S. 27, 35 (1980))).

8. Jefferson Lines, 514 U.S. at 179.

9. See Lewis, 447 U.S. at 36 (citing Hughes v. Oklahoma, 441 U.S. 322, 326 (1979).

10. See Granholm v. Heald, 544 U.S. 460, 476 (2005) (quoting Philadelphia v. New Jersey, 437 U.S. 617, 624 (1978)).

11. See Legato Vapors, LLC v. Cook, 847 F.3d 825, 830 (7th Cir. 2017) (quoting Brown-Forman Distillers Corp. v. New York State Liquor Authority, 476 U.S. 573, 578-79 (1986)) (citing Edgar v. MITE Corp., 457 U.S. 624, 642, 102 S. Ct. 2629, 73 L. Ed. 2d 269 (1982) (plurality opinion)).

12. See Hunt v. Wash. State Apple Advert. Comm’n, 432 U.S. 333, 353 (1977) (citing Dean Milk Co. v. Madison, 340 U.S., at 354) (striking down discriminatory legislation where alternative methods to serve the state’s interest were readily available).

13. See Lewis, 447 U.S. at 36 (1980) (quoting Philadelphia v. New Jersey, 437 U.S. 617, 626-27 (1978)).

14. Legato Vapors, 847 F.3d at 827 (7th Cir. 2017).

15. See Brown-Forman Distillers Corp. v. N.Y. State Liquor Auth., 476 U.S. 573, 580 (1986).

16. Healy v. Beer Institute, Inc., 491 U.S. 324, 336 (1989) (quoting Edgar v. MITE Corp., 457 U.S. 624, 642-43 (1982)); but see CTS Corp. v. Dynamics Corp. of Am., 481 U.S. 69, 89 (1987) (upholding Indiana legislation that had extraterritorial effects but was not at risk at subjecting entities to the laws of more than one state).

17. See Ass’n for Accessible Meds. v. Frosh, 887 F.3d 664, 668 (4th Cir. 2018) (citing Star Sci., Inc. v. Beales, 278 F.3d 339, 355 (4th Cir. 2002) (striking down Maryland price gouging legislation that applied extraterritorially to all upstream manufacturers and wholesalers of “essential medicines” that were made available for sale in Maryland), reh’g en banc denied, 742 F. App’x 720 (4th Cir. 2018), cert. denied, 139 S. Ct. 1168 (2019).

18. E.g., Brown-Forman Distillers Corp, 476 U.S. at 586 (1986).

19. E.g., Edgar v. MITE Corp., 457 U.S. at 645-46 (1982) (plurality opinion).

20. Compare Dep’t of Revenue v. Ass’n of Wash. Stevedoring Cos., 435 U.S. 734, 750 (1978) (upholding an unbiased tax on interstate activity that did not unfairly burden interstate commerce relative to the state’s interest in exacting its fair share of the cost of government), with Kassel v. Consol. Freightways Corp., 450 U.S. 662, 678 (1981) (holding that traditional deference to state highway safety regulations was overcome by the legislation’s substantial burden on interstate commerce and the absence of evidence of a “significant countervailing safety interest”).

21. Dep’t of Revenue v. Davis, 553 U.S. 328, 338-39 (2008) (quoting Pike v. Bruce Church, 397 U.S. 137, 338-39 (1970)).

22. Ass’n of Wash. Stevedoring Cos., 435 U.S. at 748.

23. Kassel, 450 U.S. at 670 (“[R]egulations that touch upon safety—especially highway safety—are those that ‘the Court has been most reluctant to invalidate.’” (quoting Raymond Motor Transp., Inc. v. Rice, 434 U.S. 429, 443 (1978))).

24. Ry. Express Agency, Inc. v. New York, 336 U.S. 106, 111 (1949) (“Where traffic control and the use of highways are involved . . . great leeway is allowed local authorities, even though the local regulation materially interferes with interstate commerce.”).

25. United Haulers Ass’n v. Oneida-Herkimer Solid Waste Mgmt. Auth., 550 U.S. 330, 342 (2007).

26. Id. at 342-43.

27. See Bibb v. Navajo Freight Lines, 359 U.S. 520, 528-29 (1959) (invalidating an Illinois highway safety regulation which had dubious safety benefits, was “out of line with the requirements of the other states,” and placed too heavy a burden on interstate commerce).

28. See Kassel, 450 U.S. at 670 (holding that Illinois did not present sufficient evidence to establish that its regulation furthered its purported goal of increasing highway safety).

29. See Mackey v. Montrym, 443 U.S. 1, 17 (1979) (noting that that states have a “paramount” interest in preserving the public health and safety of its residents and that the Supreme Court has traditionally granted states “great leeway” in adopting procedures to protect them.); Kassel, 450 U.S. at __ (1981) (Brennan, J., concurring) (“[I]f safety justifications are not illusory, the Court will not second-guess legislative judgment about their importance in comparison with related burdens on interstate commerce.” (quoting Raymond Motor Transp., Inc. v. Rice, 434 U.S. 429, 449-50 (1978) (Blackmun, J., concurring))); Fla. Bar v. Went for It, 515 U.S. 618, 625 (1995) (upholding the Florida Bar’s free speech restrictions on the solicitation of accident victims in order to protect the victim’s privacy)

30. Chemical Waste Management, Inc. v. Hunt, 504 U.S. 334 (1992).

31. See United Haulers Ass’n v. Oneida-Herkimer Solid Waste Mgmt. Auth., 550 U.S. 330, 347 (2007) (upholding burdensome requirements that forced all waste haulers to use a single state-run facility, despite the fact that it charged significantly higher fees than private facilities charged in the open market, because it would otherwise be “much more costly” for the state to enforce its recycling laws). It should be noted that state laws protecting a state’s environmental interests have not been traditionally been given the same deference as laws protecting their health and safety or privacy interests.

32. See Midwest Title Loans, Inc. v. Mills, 593 F.3d 660 (7th Cir. 2010) (striking down provisions of the Indiana Uniform Credit Code which regulated credit transactions made by Indiana residents “in another state,” despite the fact that Indiana had a “colorable interest in protecting its residents from the type of loan that [the title loan company] purveys”).

33. See Nat’l Elec. Mfrs. Ass’n v. Sorrell, 272 F.3d 104, 115 (2d Cir. 2001) (citing Healy v. Beer Inst., 491 U.S. 324, 332 (1989); and then citing Brown-Forman Distillers Corp. v. N.Y. State Liquor Auth., 476 U.S. 573, 582, 90 L. Ed. 2d 552, 106 S. Ct. 2080 (1986)).

34. Healy, 491 U.S. at 337.

35. 186 U.S. 380, 387 (1902).