President – Don Christensen, Colonel, U.S. Air Force (Ret.)

Don Christensen, Colonel, USAF (Ret.) served as chief prosecutor for the United States Air Force between 2010 and 2014. He served as a trial counsel, defense counsel or military judge for every year of his 23-year career in the United States Air Force.

Christensen has served as an Assistant Staff Judge Advocate, Area Defense Counsel, Circuit Defense Counsel, Deputy Chief Circuit Defense Counsel, and Deputy Staff Judge Advocate, as a deployed Staff Judge Advocate, Chief Circuit Trial Counsel, and Staff Judge Advocate and as a Military Judge. He has tried over 150 courts-martial as a trial and defense counsel and has presided over 100 trials as a military judge.

He was born in Sturgis, South Dakota and received his law degree from Marquette University Law School. A third generation Air Force officer, he received his commission as a second lieutenant through ROTC and entered active service on 15 July 1991. Christensen is licensed to practice law before the Supreme Court of Wisconsin.

Christensen has received numerous awards and decorations including the Legion of Merit, the Meritorious Service Medal, the Air Force Commendation Medal, and the Air Force Achievement Medal.

Download Christensen’s Military Bio (PDF)

Program and Policy Director – Christina Knowles

Christina M. Knowles has over a decade of experience in public policy, government affairs, and nonprofit and public sector executive management. Christina has expertise on a variety of gender equality issues, and advancing the status of women and girls is her life’s calling.

Prior to joining Protect Our Defenders, Christina was a fixture on the Massachusetts political scene and was named a “Top 100 Influencer” by Campaigns and Elections magazine. She has been at the helm of several organizations, including serving as the State Director of the National Organization for Women, Massachusetts and as Executive Director of the Boston Women’s Workforce Council, Mayor Martin J. Walsh’s groundbreaking initiative to end the wage gap. Christina also worked in the MA State House as a Legislative Aide, Chief of Staff, and Executive Director of the Caucus of Women Legislators.

Christina has held key leadership positions in many legislative campaigns, and is particularly proud of her role in passing laws on paid sick leave, equal pay, transgender equal rights, and banning the shackling and restraint of pregnant inmates. She has extensive electoral experience, is a 2010 Emerge Massachusetts graduate, and contributed to the book, 51%: Woman and the Future of Politics.

Christina serves on numerous boards of directors, and was the founding co-chair of UMass Women into Leadership, which trains women undergraduates for public service leadership careers. Christina received her graduate degree from UMass Boston’s Women in Politics and Public Policy Program and her B.A. in Women’s Studies and English from UMass Amherst.

Communications Director – Brian Purchia

Brian Purchia is the Communications Director for Protect Our Defenders and has been with the organization since its launch. Described by Craigslist founder Craig Newmark as “genuinely innovative,” Brian has served as a news media adviser and spokesman for former San Francisco Mayor Gavin Newsom,, Green For All and other social change organizations. Brian was described by the San Francisco Chronicle as Newsom’s “go-to guy for social media” for his implementation of a groundbreaking new media strategy called “gutsy” and “brilliant” on NPR.

In Newsom’s new book Citizenville, the current Lt. Gov. of California says, “as I started my second term as San Francisco Mayor I was dismayed as how far behind we still were technologically. Police cars weren’t equipped for email. City websites weren’t set up to take meaningful feedback online. We were surrounded by some of the best and brightest minds technology, but were still operating as though we were in a time warp. I hired a former Voice of America reporter named Brian Purchia as my new media director and asked him if he could figure out how to fix this problem. That was the beginning of a two-year period in which we transformed our city government. We started digitizing, mashing up, and opening up everything we possibly could — far beyond what I had initially imagined when I brought Brian in.”

Brian is recognized as a “Gov 2.0” leader for his work to improve civic engagement by making government more accessible through tapping into the power of social media. Before working in government and for social change organizations, Brian worked in media, as a reporter in Washington, DC.

Advocacy and Program Associate – Angela Lee

Angela Lee is the Advocacy and Program Associate for Protect Our Defenders. She has a Masters degree in Criminology from George Washington University, where she was awarded both a University Fellowship and a Graduate Assistantship. She also won the Graduate Excellence in Research and Writing Award for her Master’s thesis on media representations of police violence.

Previously, Angela served as the Communications Director for SurvJustice, an organization that focuses on campus sexual violence issues. Working to advocate for sexual assault survivors reinforced Angela’s passion for improving policies that impact them, and she joins Protect Our Defenders, eager to continue this work.

Prior to moving to Washington, D.C., Angela worked in the editorial and marketing departments at Mochi Magazine, which is geared towards Asian American readers. At Mochi, Angela served as a copy editor and also wrote articles on a variety of topics, such as gender issues and the stigma of HIV among Asian women. She later transitioned to the marketing department where she was responsible for developing and implementing strategies to increase readership. In 2008, Angela earned her B.A. from Boston University in International Relations and minor in Journalism.

Communications Manager – Max Wertheimer

Max comes to Protect Our Defenders with experience in communications, social media, and public policy. He has previously worked in the Office of Government Affairs for San Francisco Mayor Gavin Newsom. Max has also worked at Burson-Marsteller, a global public relations firm, specializing in crisis communications. Throughout his career, Max has worked for political campaigns, advocacy organizations, government agencies, technology companies, labor unions, law firms, and telecommunications companies.

Pro Bono Program Assistant – Adelaide Kahn

Adelaide Kahn joined Protect Our Defenders in 2017 as a Pro Bono Program Assistant. Having received her Master’s degree in Criminology from George Washington University, Adelaide is pursuing her passion to advocate for victims of injustice. She worked for various non-profit organizations before joining POD, including the Family Court Assistance Project at the University of Wisconsin-Madison Law School and the Los Angeles J. Paul Getty Museum. At the Family Court Assistance Project, Adelaide worked to place potential clients with lawyers and law students offering pro bono legal assistance to the larger Madison community. Although hailing from Los Angeles, CA, Adelaide received her Bachelor of Arts degree in International Relations with a focus on global security from the University of Wisconsin-Madison in 2012.