By Alexis Carmichael
Introduction and Background
The beginning of 2016 brought an unprecedented wave of climate change lawsuits.[1] Municipalities, local governments, and state administrations reached their breaking point with oil and gas conglomerates.[2] In response, several municipalities, as illustrated through subsequent cases, strategically chose to file suit, holding the oil industry legally responsible for the daily burning of fossil fuels that caused environmental devastation to their local communities.[3]
Municipalities primarily bring suit against major oil and gas companies, such as ExxonMobil and Chevron.[4] However, some municipalities implicate not only oil giants but also local oil refineries.[5] Plaintiffs are pursuing litigation on the grounds that oil and gas conglomerates knew or should have known about their role and contributions to the climate change crisis.[6] For instance, plaintiffs in the case of City & County of Honolulu v. Sunoco LP assert that the oil and gas companies misrepresented their products and daily functions of their businesses; therefore, they are the ones to blame for global warming.[7]
According to a 2023 report, climate change litigation filings have grown over the last decade.[8] Many of these cases are reaching the litigation phase. However, the proceedings are being prolonged due to jurisdictional battles and are garnering significant media coverage, thereby inspiring potential plaintiffs to take legal action. As of the beginning of 2023, 2,180 climate change cases were filed internationally, while over half (1,522) were filed in the United States.[9] In 2023, over 230 more climate change cases were filed worldwide.[10] These cases attract significant attention in cities located in states such as California, Colorado, and Hawaii.[11] The following Blog Post examines cases that emphasize the devastating impacts of climate change on communities, detailing the legal claims brought against Big Oil and the damages being sought.
A. Mayor of Baltimore v. BP P.L.C.
Mayor of Baltimore v. BP P.L.C. serves as the catalyst for a host of subsequent climate change lawsuits.[12] In 2018, Baltimore’s Mayor and City Council asserted causes of action for public nuisance, private nuisance, strict liability failure to warn, strict liability design defect, negligent design defect, negligent failure to warn, and trespass, as well as a cause of action under Maryland’s Consumer Protection Act.[13] Ultimately, the complaint alleges that the companies concealed the environmental impacts of the fossil fuels they promoted.[14] The environmental changes that allegedly impacted the city included higher sea levels, increased flooding, and more frequent and intense heat waves.[15]
While the oil and gas companies often remove to federal courts, local municipalities often seek state remedies in their local jurisdiction. The oil and gas companies invoke several grounds for federal jurisdiction, such as the federal officer removal statute (28 U.S.C. § 1442) and the Enclave Clause of the U.S. Constitution.[16] As previously mentioned, municipalities are suing under state law in these suits.[17] The main laws cited are public nuisance laws, which are generally anything that interferes with the rights of the public.[18] The remedies that municipalities are seeking are in the billions.[19] For instance, per Mayor of Baltimore v. BP P.L.C., plaintiffs seek to hold defendants liable for billions of dollars in compensatory damages, punitive damages, and disgorgement of profit.[20] Additionally, they request injunctive relief and abatement of emissions from fossil fuel-fired power plants.[21]
B. City & County of Honolulu v. Sunoco LP
In 2020, Honolulu government entities sued major oil and gas companies such as Sunoco LP, Exxon Mobil, and Chevron for misleading the public regarding climate-related risks associated with fuels and products.[22] “Honolulu asserted claims of public nuisance, private nuisance, strict liability for failure to warn, negligent failure to warn, and trespass. The City seeks compensatory damages; equitable relief, including abatement of the nuisance; punitive damages; disgorgement of profits; attorneys’ fees; and costs of suit.”[23]
The environmental devastation allegedly caused by climate effects includes sea level rise and coastal erosion, changes in precipitation patterns, and increased heat waves.[24] The plaintiffs claimed that the rise in sea level and coastal erosion have had a direct impact on Hawaii’s tourism revenue.[25] Further, the precipitation pattern changes have impacted freshwater availability in ecosystems, according to the plaintiffs.[26]
Defendants removed the case to federal court, arguing that the case should be heard under the Clean Air Act.[27] Essentially, the defendants denied liability and argued that this lawsuit was just another “in a long line of lawsuits seeking to regulate interstate and international greenhouse gas emissions,” which are caused by “billions of daily choices, over more than a century, by governments, companies, and individuals.”[28]
The Supreme Court of Hawaii allowed the state claims to prevail, finding that the claims “arose out of” and “relate[d] to” the companies’ sale and marketing of products in Hawaii.[29] In other words, the extraction, production, marketing, and sale of products such as oil, natural gas, and coal contributed to deceptive practices intended to downplay climate effects in Honolulu.[30]Furthermore, the U.S. Supreme Court denied the removal from state to federal court, therefore moving the case closer to trial.[31] As of early 2025, the case has moved to the discovery phase in state court.[32]
C. The People of the State of California v. Exxon Mobil Corporation et al.
In November 2024, California Attorney General Rob Bonta filed a complaint against ExxonMobil, alleging that the company “caused or substantially contributed to the deluge of plastic pollution that has harmed and continues to harm California’s environment, wildlife, natural resources, and people.”[33] Furthermore, the complaint asserted that ExxonMobil deceived California residents “by promising that recycling could and would solve the ever-growing plastic waste crisis” and that recycling was expected to reduce greenhouse gas emissions, which California alleged was based on “selective data presentation and problematic assumptions that mislead consumers.”[34]
The California Attorney General asked the Court to compel the defendants to eliminate the effects of the public nuisance by ordering ExxonMobil to establish an abatement fund and refrain ExxonMobil from making public statements regarding “advanced recycling.”[35] Additional relief sought included temporary and permanent equitable relief to prevent pollution, impairment, and destruction of natural resources, as well as civil penalties and disgorgement.[36]
Conclusion
These three cases demonstrate that communities are growing increasingly frustrated with the environmental devastation caused by climate change. Greenhouse gas emissions, which are linked to the activities of major oil and gas companies, are contributing to climate change. However, there is a balance between holding oil conglomerates accountable and maintaining consistent oil production. Nevertheless, the question remains: At what rate can companies efficiently produce while continuing to degrade local communities environmentally? As climate and weather patterns continue to shift and become more unpredictable, climate change lawsuits will become more prevalent and common in our court system. Eventually, courts will need to develop a framework that addresses how to navigate this legal challenge while keeping each party’s interest in mind.
Copyright 2025, by Alexis Carmichael.
[1] See Chris McGreal & Alvin Chang, How Cities and States Could Finally Hold Fossil Fuel Companies Accountable, The Guardian (June 30, 2021), https://www.theguardian.com/environment/ng-interactive/2021/jun/30/climate-crimes-fossil-fuels-cities-states-interactive [https://perma.cc/4M95-UDNA].
[2] See id.
[3] See id.
[4] See generally Mayor of Balt. v. BP P.L.C. No. 18-2357, 2019 U.S. Dist. LEXIS 97438, at *1 (D. Md. June 10, 2019).
[5] See id.
[6] See generally Complaint at 2, 35, City & County of Honolulu v. Sunoco LP, No. 1CCV-20-0000380 (Haw. Cir. Ct. filed Mar. 9, 2020), https://climatecasechart.com/wp-content/uploads/case-documents/2020/20200309_docket-1CCV-20-0000380_complaint.pdf [https://perma.cc/9MPH-K2JA] [hereinafter City & County of Honolulu Complaint].
[7] See generally id. at 2, 4.
[8] See generally Renee Cho, Climate Lawsuits Are on the Rise. This Is What They’re Based On., Colum. Climate Sch.: Climate, Earth, and Soc’y (Aug. 9, 2023), https://news.climate.columbia.edu/2023/08/09/climate-lawsuits-are-on-the-rise-this-is-what-theyre-based-on/ [https://perma.cc/S8PP-YPJM] (citing Michael Burger & Maria Tigre, Global Climate Litigation Report: 2023 Status Review (Sabin Center for Climate Change Law, Columbia Law School & United Nations Environment Programme, 2023)).
[9] Id.
[10] Global Trends in Climate Change Litigation: 2024 Snapshot, London Sch. of Econ. & Pol. Sci. (June 27, 2024), https://www.lse.ac.uk/granthaminstitute/publication/global-trends-in-climate-change-litigation-2024-snapshot/ [https://perma.cc/QH92-NKWR].
[11] Cho, supra note 8.
[12] See generally Mayor of Balt. v. BP P.L.C., No. 18-2357, 2019 U.S. Dist. LEXIS 97438 (D. Md. June 10, 2019).
[13] Id. at *7.
[14] See id. at *55; see generally Complaint at 1, Mayor of Balt., No. 24-C-18-004219 (Md. Cir. Ct. filed July 20, 2018), https://climatecasechart.com/wp-content/uploads/case-documents/2018/20180720_docket-24-C-18-004219_complaint.pdf [https://perma.cc/3SXW-6VLX] [hereinafter Mayor of Balt. Complaint].
[15] Mayor of Balt., 2019 U.S. Dist. LEXIS 97438, at *6–7.
[16] Id. at *41–47, *51–57.
[17] See generally id. at *7.
[18] Id.
[19] See generally Rich Pedroncelli, Who Should Pay Billions for Climate Disasters? California and Others Target Big Oil — Will That Work?, Capradio (Mar. 4, 2025), https://www.capradio.org/articles/2025/03/04/who-should-pay-billions-for-climate-disasters-california-and-others-target-big-oil-will-that-work/#:~:text=In%20Oregon’s%20Multnomah%20County%2C%20a,a%20%2450%20billion%20abatement%20fund [https://perma.cc/5MZ2-4VEW].
[20] Mayor of Balt. Complaint, supra note 14, at 130.
[21] Id.
[22] See City & County of Honolulu v. Sunoco LP, 537 P.3d 1173, 1182 (Haw. 2023); see also J. Michael Showalter, ESG Litigation Update: Hawaii Supreme Court Allows Petroleum Industry Climate Case to Proceed, Nat’l L. Rev. (Nov. 15, 2023), https://natlawreview.com/article/esg-litigation-update-hawaii-supreme-court-allows-petroleum-industry-climate-case [https://perma.cc/FJQ7-92D6].
[23] City & County of Honolulu v. Sunoco LP, Climate Case Chart, https://climatecasechart.com/case/city-county-of-honolulu-v-sunoco-lp/ [https://perma.cc/2CZ2-XH5N] (last visited Mar. 30, 2025) (providing a summary of the Complaint filed Mar. 9, 2020); see also City & County of Honolulu Complaint, supra note 6, at 113.
[24] See City & County of Honolulu Complaint, supra note 6, at 2, 55, 90–91.
[25] City & County of Honolulu, 537 P.3d at 1183–84.
[26] Id.
[27] Notice of Removal at 28, City & County of Honolulu, No. 1:20-cv-00163 (D. Haw. filed Apr. 15, 2020), https://climatecasechart.com/wp-content/uploads/case-documents/2020/20200415_docket-120-cv-00163_notice-of-removal.pdf [https://perma.cc/H9EJ-3XVF].
[28] City & County of Honolulu, 537 P.3d at 1185; Showalter, supra note 22.
[29] City & County of Honolulu, 537 P.3d at 1184; Showalter, supra note 22.
[30] See generally City & County of Honolulu, 537 P.3d at 1183–84; Showalter, supra note 22.
[31] See Supreme Court Denies Big Oil’s Attempts to Escape Accountability in Hawai`i, Ctr. for Climate Integrity (Jan. 13, 2025), https://climateintegrity.org/news/view/supreme-court-denies-big-oils-attempts-to-escape-accountability-in-hawaii [https://perma.cc/7UZ2-L55R].
[32] Id.
[33] Complaint for Abatement, Equitable Relief, and Civil Penalties at 7, People v. Exxon Mobil Corp., No. CGC24618323 (Cal. Sup. Ct. filed Sept. 23, 2024), https://climatecasechart.com/wp-content/uploads/case-documents/2024/20240923_docket-CGC24618323_complaint.pdf [https://perma.cc/ZV63-P5CV].
[34] Id. at 7, 89.
[35] Id. at 145.
[36] Id. at 145–46.
