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Mariel Montero

Public Policy Coordinator

she/her

Mariel is a Texas native who received a B.A. from Amherst College and an M.A. in International Policy and Development from the Middlebury Institute. While completing her Master degree, Mariel spent semesters interning at the International Organization of Migration and the HOPE Border Institute, conducting immigration policy research and strengthening service networks for asylum seekers in the U.S.

Mariel’s diverse background includes work with migrant advocacy organizations, progressive political campaigns, English language instruction abroad, and roles in local, state, and federal government. Her multidisciplinary expertise reflects a deep commitment to advancing equitable policies, safeguarding the separation of church and state, and fostering meaningful change.

THE LATEST FROM

Mariel Montero

They’re not hiding it anymore: Trump’s Religious Liberty Commission’s true agenda

September 30, 2025
Mariel Montero

PragerU’s Christian Nationalist agenda threatens to reshape public education

August 25, 2025
Mariel Montero

This Public Schools Week, help us fight private school vouchers across the country

February 24, 2025
Mariel Montero
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Americans United for Separation of Church and State is a nonpartisan, not-for-profit educational and advocacy organization that brings together people of all religions and none to protect the right of everyone to believe as they want — and stop anyone from using their beliefs to harm others. We fight in the courts, legislatures, and the public square for freedom without favor and equality without exception.

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