CRISPR-Cas is a gene editing technology that can strengthen a defense countermeasure against an infectious pathogen and can heighten the attack risk of an engineered pathogen. The purpose of this report is twofold: to analyze the advantages of CRISPR for participants within a strategic environment, such as rogue, non-state attackers and defenders coordinated between nation-states and other entities, and to identify the ways in which CRISPR configures a defender’s countermeasure against a biological event. In its assessment, this report utilizes the case study of COVID-19 to examine the applications of CRISPR-Cas systems to SARS-CoV-2. This report finds that CRISPR reduces some barriers to entry and exacerbates the possibility for malicious non-state attackers to engineer a pathogen and engender a serious biological event in the very short-term. However, key barriers to entry will continue to pose challenges to attackers comparative to defenders. In this report, “attacker” refers to non-state actors maliciously using CRISPR to engender a biological event while “defender” refers to coordinated entities responding to biological events, whether natural or deliberate. In the short- to mid-term, the use of CRISPR-Cas systems in designing a countermeasure against a biological event is to the advantage of the defender. CRISPR offers more accessible, rapid, and convenient diagnostic testing; a quick and accurate platform to identify viral vectors; and the potential for antiviral therapy. Through enactment of certain policy configurations, the comparative advantage of CRISPR may decisively shift to the defender, including in the very short-term.