Learn about the Des Moines County Attorney's Office staff members, including the County Attorney.
Lisa Schaefer
County Attorney
Bio
Lisa Schaefer
Ms. Schaefer graduated from the University of Iowa in 1992 with a Bachelor of Arts Degree in Political Science with a minors in Sociology and History. She then worked as a victim advocate for survivors of domestic violence and sexual assault before entering law school in 1998. She graduated from the University of Iowa College of Law in 2001 with Distinction and was admitted to the Iowa Bar later that year.
After a brief time clerking for the 7 th Judicial District of Iowa and a year in private practice, she joined the Des Moines County Attorney’s Office in 2003 where she prosecuted sexual abuse and child endangerment cases, as well as other felonies. She left the office in 2011 to teach in the Law Enforcement and Justice Administration program at Western Illinois University. However, her passion for serving her community in the area of prosecution, led her to run for Des Moines County Attorney in 2018. She took office in 2019.
Erin Stensvaag
Erin Stensvaag is the Assistant County Attorney assigned to Child in Need of Assistance and mental health cases. She graduated from Buena Vista University in 2007 and the University of Iowa Law School in 2010. She has been a licensed attorney in good standing since 2010.
After working at the Henry County Attorney’s Office for six years after graduation, she began working in Des Moines County in 2017.
Trent Henkelvig
Trent Henkelvig is an Iowa native born and raised in Algona, Iowa graduating from Bishop Garrigan High School in 1992. From that point he enlisted in the Army where he spent 4 years in the 82nd Airborne. After completion of his first tour on active duty he enlisted in the National Guard where he served the remainder of his twenty-year career.
He graduated from Drake Law School in 2007 and was admitted into the Iowa Bar in 2009 at which time he was in private practice from 2009 -2021 when he accepted a position with the Des Moines County Attorney’s Office.
Cassie Kilby
Cassie Kilby initially joined our team in in August of 2024 as a Law Clerk shortly after graduating law school. Cassie is a graduate of the University of Iowa College of Law. She passed the Iowa bar examination in the Spring of 2025. Cassie handles misdemeanor prosecutions. She also oversees the School Bus Deferred Prosecution Program, as well as the Truancy Program.
Blake Vierra
Blake J. Vierra graduated from Syracuse University College of Law in 2017. Shortly after graduating law school, he worked as a public defender in Waterloo Iowa for three years before joining the Henry County Attorney's Office in 2021. Blake prosecuted felony sexual abuse cases as well as all cases involving children, including Child in Need of Assistance cases as well as juvenile delinquencies in Henry County. Blake continues to prosecute felony sexual abuse cases in Des Moines County.
