Congratulations to our newest PhD graduate, Dr. Carolyn Eckert, who successfully defended her dissertation, "Punctuated Ethos: Addressing Trust, Credibility and Expertise in Times of Crisis." The dissertation supervisor was Dr. Ashley Mehlenbacher and the readers were Dr. Heather Love and Dr. Brianna Wiens. The external examiner was Dr. Nathan Johnson and the internal/external examiner was Dr. Elena Neiterman. The defence was chaired by Dr. Mark Crowley.
Abstract
Trust, the earning, sustaining, and loss of it, is at the center of public responses during a health crisis like the COVID-19 pandemic. This dissertation explores how trust functions not merely as a social or institutional ideal, but as a rhetorical construct negotiated through language, ethos, and public discourse. Drawing on rhetorical theories of ethos, from Aristotle’s character-based model to Hyde’s concept of ethos as dwelling, the project introduces the concept of “punctuated ethos” to analyze how rhetorical credibility is constructed, fractured, and recalibrated at key moments of crisis. Through a rhetorical analysis of Canadian responses to COVID-19, grounded in a corpus of local news media coverage, this study investigates how political and public health authorities communicated protective measures such as lockdowns and vaccination campaigns, and how acts of resistance, such as the Trinity Bible Chapel (2020-2021) defiance and the Freedom Convoy (2022) protest, contested institutional credibility and reshaped public narratives of trust.
In early 2020, Canadian acceptance of public health measures was initially high. However, prolonged lockdowns, pandemic fatigue, and vaccine controversies fractured public trust, leading to increased polarization and protest. Emerging communication technologies further complicated trust-building by amplifying mis/disinformation and undermining traditional media authority. This dissertation applies a rhetorical approach to health risk communication frameworks (Leiss, 2004; Witte, 1992), alongside theoretical tools such as Huiling Ding’s epidemic rhetoric (2014), Stephen Katz and Carolyn Miller’s rhetorical model of risk communication (1996), and rhetorical analyses of appeals, topoi, and public argumentation (Fahnestock, 1998; Miller, 1989; Perelman, 1982; Sontag, 1978, Bitzer, 1968; Goodnight, 1982; Burke, 1969). These frameworks support an examination of how the public validates expertise (Mehlenbacher, 2022) and how trust becomes rhetorically shaped, disrupted, or re-established in moments of crisis.
Chapter 2 offers a historical context for Canada’s public health communication, from the 1918 influenza pandemic through SARS (2003) and H1N1 (2009), showing how trust was constructed, destabilized, and unevenly distributed across racialized and marginalized communities. Chapter 3 surveys relevant rhetorical, medical, and communication literatures, framing trust as a contingent rhetorical achievement rather than a stable condition. Chapters 4, 5, and 6 form the core case studies, analyzing pandemic rhetoric, vaccine rhetoric, and protest rhetoric, respectively, each applying grounded theory and rhetorical analysis to trace how communicators used strategies like fear, hope, and ethos to shape audience responses. These chapters also identify the shifting roles of local media as amplifier, skeptic, or translator of public health messages. The final chapter proposes a symbolic formulaic framework to model how emotional appeals, perceived efficacy, and media functions interact rhetorically to either sustain or fracture public trust.
Key findings highlight the importance of localized, community-centered messaging, the strategic use of emotional appeals, and the need for credible, transparent communication. Public health communicators must anticipate rhetorical outcomes by aligning emotional resonance with timing (kairos), community values (topos), and credible ethos. This research underscores that rhetoric is not an afterthought in crisis communication, it is the mechanism through which trust is built, challenged, or lost. Grounded in rhetorical theory and applied to contemporary media and health contexts, this dissertation offers actionable strategies for health professionals, educators, journalists, and policymakers to design resilient, trustworthy communication in times of crisis.