Sampson's prominence in the anti-vaccination movement in Maine began with her 2019 opposition toward legislation eliminating religious and philosophical exemptions to childhood vaccinations in the state.

[9] During the 130th Maine state legislature (2021-2022) Sampson voted No against issues involving Wabanaki Rights, including LD 906: An Act To Provide Passamaquoddy Tribal Members Access to Clean Drinking Water, and LD 585: An Act To Enhance Tribal-State Collaboration, To Revise the Tax Laws Regarding the Houlton Band of Maliseet Indians, the Passamaquoddy Tribe and the Penobscot Nation and To Authorize Casinos, Off-track Betting Facilities, Federally Recognized Indian Tribes and Certain Commercial Tracks To Conduct Sports Wagering.

[11] When the bill passed into law, she joined state anti-vaccine activists in an effort to collect enough voter signatures for a people's veto of the new legislation to appear on a statewide ballot.

The group successfully collected the signatures, and Sampson spoke at a November 2019 "Vaccine Injury Epidemic Event" rally in Washington, D.C. to promote and celebrate the veto's advancement.

[13] Sampson was a headlined speaker at a July 2021 event in Belfast, Maine co-sponsored by conspiracy theorist and Holocaust denier Robert David Steele.

During the event, Sampson promoted an audit of Maine's presidential election results and urged attendees to continue participating in protests against COVID-19 mitigation measures such as masking, lockdowns and vaccination.