Meet the Staff

Portland City Hall
The Office of Government Relations staff maintain hybrid (remote and on-site) work schedules. Please contact staff in advance if planning to visit the office in-person.
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Sam Chase (he/him), Director

Sam is the Director for the Office of Government Relations. Previously, Sam served as an elected member on Metro Council, Chief of Staff to former Commissioner Nick Fish, and as an executive director for housing and health nonprofits. Sam has worked as an advocate to address poverty and create inclusive communities with living-wage jobs, affordable housing, homeless services, and environmental protections. He enjoys flyfishing, hiking, camping, and most of all spending time with his very busy, blended family of six.

Nils Tillstrom (he/him), Deputy Director & Regional Liaison

Nils is the Deputy Director and Regional Liaison for the Office of Government Relations (OGR). Prior to joining the office, he spent six years working on Capitol Hill in Oregon’s congressional delegation. Nils is most excited to be working with smart, energetic colleagues in OGR and across the City on issues related to Portland’s most vital priorities. When he is not working, Nils enjoys being outdoors with his wife and daughter.

International Relations

Chido Dhliwayo (she/her), International Relations Director

Chido joined the Office of Government Relations as a Hatfield Fellow and now, as International Relations Director, she serves as the City’s conduit to Portland’s local-international community. As International Relations Director, she helps to ensure the City of Portland is poised to capitalize on opportunities for existing and new international partnerships around culture, business, education, policy objectives, as well as Portland’s sister city relationships. Chido was born and raised in Zimbabwe and couldn’t be happier to contribute in helping to make Portland a more welcoming international city for all.

Tribal Relations

Adam Becenti (Hastiin Becenti, he/him), Tribal Relations Program Manager 

Adam Becenti (Diné/Navajo) is Tsi’naa jinii, Black Streak Wood People and born for the Tsé Nahabiłnii, Sleep Rock People Clan. Becenti grew up in Gallup, New Mexico and moved to Portland 11 years ago. He holds a Bachelor's Degree in Psychology and Ethnic Studies from the University of Colorado at Boulder, and a Master's Degree in Public Policy from the University of Michigan Ann Arbor. Tribal relations and engagement work is critical on how government functions to ensure equitable access, inclusion, and positive outcomes for Tribes and American Indian/Alaska Native peoples. As Tribal Relations Program Manager, Adam will serve U.S. Tribal Governments and the Portland Urban Indian Community in leading and creating a vision with Tribes and Tribal community on how Portland can best serve Tribes and American Indian/Alaska Native peoples. In his spare time, Adam enjoys outrigger canoeing, being plant-forward, and sci-fi movies. He once did the haka with Maori warriors during the annual Waitangi celebration in New Zealand. 

Federal Relations

Jack Arriaga (he/him), Federal Government Relations Manager

Jack is the Federal Government Relations Manager for the Office of Government Relations (OGR). Prior to joining the OGR, Jack worked in Washington, D.C. as a senior aide within Oregon's congressional delegation. As the City's primary liaison to our federal representatives, he enjoys finding creative ways to make the important work happening in our nation's capital feel a little closer to home. Jack has a broad range of political, campaign, and policy experience that includes health care, housing, immigration, and technology issues. Having grown up in Oregon, Jack attended Gonzaga University where he majored in Political Science.

State Relations

Evyn Mitchell (she/her), State Government Relations Manager

Evyn is the State Government Relations Manager for the Office of Government Relations. She brings a background in collaborative process, advocacy and campaign and nonprofit fundraising and management. Her experience includes leading public affairs for a suite of special districts, collaborative problem-solving and advocacy on behalf of Oregon’s counties, and running congressional, statewide, municipal, and ballot measure campaigns in Oregon. At home, Evyn can be found playing with her toddler, working in the garden, enjoying live music, and snuggling with her ancient cat and matching ten-pound dog

Derek Bradley (he/him), State Lobbyist


Derek is the State Lobbyist for the Office of Government Relations (OGR). Prior to joining OGR, he served for four years working with former Commissioner Jo Ann Hardesty first as her Policy Director and then as her Chief of Staff. He has previous government experience working as a clerk for a Multnomah County Judge as well as a Legislative Assistant for a State Representative. He has a BA in Political Science from Reed College and a JD from Lewis and Clark Law School with a focus in environmental law. In his free time Derek enjoys going to the gym, adventures with friends, and exploring Portland’s food scene. 

Emily Pfeiffer (she/her), State Associate

Emily is the State Associate for the Office of Government Relations (OGR) and is passionate about making Portland a better city for all. She brings a background in campaign management and legislative work. Prior to joining OGR, Emily worked as the Finance Director and Operations Director for Future PAC and has worked for multiple State Representatives, including Representative Rob Nosse. Outside of the office, Emily loves reading, enjoying live music, and cuddling with her cat, Blanche.

Grant Opportunities & Advancement Team (GOAT)

Kari Schlosshauer (she/her), Senior Research & Communications Associate


Kari is the Senior Research & Communications Associate for the Office of Government Relations. She leads strategy efforts through research, analysis, communication, and citywide coordination. Kari graduated from Antioch University Seattle with a Master's in Environment and Community, and she also holds a Certificate in Public Administration from Portland State University. In her free time, Kari devours books, nurtures the garden, plans her next coastal getaway, and watches a lot of soccer. 

Haley Tortorella (she/they), Research & Communications Associate

Haley is the Research and Communications Associate for the Office of Government Relations. Her portfolio includes culture, livability, community, economic development, and technology. She began her work with the City of Portland in 2019 as a state lobbyist and has a background in campaign finance and policy. Through these years of experience, she continues to find service to her community and undoing past harms to marginalized groups as her passion and foundation. Outside of work, Haley spends her time exploring Oregon’s natural beauty with her companion, Zucchini, her beloved chocolate Labrador Retriever.

Administrative Team

Susan Dietz (she/her), Business Operations Manager

Susan is the Business Operations Manager for the Office of Government Relations. As part of the administrative team, she supports budgeting, financial management, human resource matters and other operational functions. Susan is driven by upholding the City’s Core Values, and focusing on fiscal responsibility. She holds a bachelor’s degree in Business Administration with a focus in Marketing. Her interests include spending time in the kitchen and being with family and friends.

Mila Greisen (she/her), Executive Assistant

Mila serves as the Executive Assistant for the Office of Government Relations (OGR). She manages the Director’s calendar, Public Records Requests, the office’s Continuity of Operations Plan and provides administrative support to the OGR team. Mila focuses on making systems work efficiently. She is a graduate of Portland State University and has a Bachelor of Arts in Anthropology. In her free time she likes to travel the world and explore trails around the Portland Metro region.