Ms. McCaskill graduated with a Bachelor of Science in political science from Arizona State University in 1998 and with a Juris Doctor from Seattle University School of Law in 2002.

Ms. McCaskill's background is in civil litigation, having defended school districts, municipalities, and the Roman Catholic Church. She has also represented clients in the areas of complex product liability and personal injury. Currently, Ms. McCaskill's practice is primarily devoted to the representation of insurance carriers, self-insured entities and third-party administrators in workers' compensation-related litigation in Arizona.

Ms. McCaskill has been admitted to practice before all Arizona and Washington state courts and the United States District Court for the District of Arizona, United States Court of Appeals for the Ninth District, United States District Court for the Eastern District of Washington, and United States District Court for the Western District of Washington. She is a member of the Arizona Workers' Compensation Claims Association, Maricopa County Bar Association, and the Scottsdale Bar Association.