Overview
Debbie grew up watching her father practice law and saw how he helped people resolve their problems. He inspired her to become a lawyer and he still inspires her today more than 25 years into her own career.
Debbie advises and defends clients in various industries, including financial institutions, health care and general corporate. With a particular focus on employment litigation and counseling, Debbie represents management in a variety of matters, including defending clients in administrative proceedings and against discrimination, wage and hour violations and retaliation claims. She has obtained numerous favorable summary judgment rulings in such cases. She also prosecutes and defends claims involving non-compete and non-solicitation agreements, misappropriation of trade secrets, and other forms of unfair competition. She defends collective and class actions, including FLSA collective actions. She also has versatility in a wide range of other commercial litigation matters, including shareholder, contract and other business disputes, antitrust issues, financial institution liability, fiduciary liability, and securities fraud.
Debbie also assists employers with compliance and employment issues under federal, state and local law, including Title VII, ADA, ADEA, FLSA, FMLA, and WARN. She counsels and assists employers in investigations stemming from employee misconduct and employee complaints under federal and state statutes. She regularly reviews, revises and drafts employee handbooks, employment policies and procedures, employment agreements, severance and retention agreements, non-compete and non-solicitation agreements and other employment related documents.
Debbie has handled numerous appeals before state and federal courts. She is the author of a number of published appellate opinions and has presented oral argument to the Seventh Circuit Court of Appeals. Debbie has jury and bench trial experience. Recognizing that trials involve risk and expense, clients sometimes prefer a form of alternative dispute resolution and, she often represents clients in mediation and arbitration. She also represents employers in proceedings before the Equal Employment Opportunity Commission, the U.S. Department of Labor, U.S. Department of Housing and Urban Development, and the Indiana Civil Rights Commission, among other agencies.
Experience
Membership & Involvement
- Member: Hancock County Bar Association; Indiana State Bar Association; Indianapolis Bar Association; Indianapolis Law Club; Society for Human Resource Management
Honors
- Martindale-Hubbell AV® Preeminent™ rated
- Selected to The Best Lawyers in America® in Commercial Litigation: 2024, 2025
- Selected to The Best Lawyers in America® in Litigation - Labor and Employment: 2024, 2025
- Selected to the Indiana Super Lawyers "Rising Star" list: 2009
Resources & Insights
Alerts
Speaking Engagements
Published Works
Blog Posts
Firm News
- Common FLSA Mistakes and Misconceptions About Overtime PayCommon FLSA Mistakes and Misconceptions About Overtime Pay
Debra Mastrian's article in the Sept./Oct. 2024 issue of Hoosier Banker provides an overview of the common mistakes employers make and misconceptions about how overtime laws apply to nonexempt employees in Indiana, as well as practical guidance for avoiding these mistakes.
- 108 Amundsen Davis Attorneys Recognized by Best Lawyers® in 2025 in America108 Amundsen Davis Attorneys Recognized by Best Lawyers® in 2025 in America
We are proud to congratulate 108 of our attorneys on being recognized by Best Lawyers® in 2025 in America.
- 88 Amundsen Davis Attorneys Recognized by Best Lawyers® in 2024 in America88 Amundsen Davis Attorneys Recognized by Best Lawyers® in 2024 in America
We are extremely excited to congratulate 88 of our attorneys on being recognized by Best Lawyers® in 2024 in America.
- EEOC's Updated Guidance on Workplace HarassmentEEOC's Updated Guidance on Workplace Harassment
Debbie Mastrian's article in the July/ August 2024 issue of Hoosier Banker provides points on several key takeaways from the new guidance and recommends employers to update their harassment policies to include examples of conduct that are acceptable.
Services
- Appellate
- Banking & Finance
- Business Litigation
- Class Action
- Employment Advice & Counsel
- Employment Litigation
- Equal Pay Compliance
- Health Care
- Labor, Employment & Immigration
- Mandatory Training
- Unfair Competition Counseling & Litigation
- Vaccine Mandates in the Workplace
- Wage & Hour
- Workplace Investigations
Education
Valparaiso University School of Law, J.D., 1994, summa cum laude
Franklin College, B.A., 1991, summa cum laude
Admissions
- Indiana
- U.S. Court of Appeals, Seventh Circuit
- U.S. District Court, Northern and Southern Districts of Indiana