She was a leading advocate of Norwegian independence from Sweden and took on representative duties for Norway during her husband's tenure as Prime Minister.

She joined Skuld, a discussion group for female students, in 1883, and was one of the co-founders of the Norwegian Association for Women's Rights (Kvindesagsforening) in 1884.

She petitioned the parliament to formalise vocational education for women by creating training courses for maids, seamstresses, cooks and housewives.

[2] Under Blehr's leadership, the association also advocated for equal pay and for children born out of wedlock to have their paternity recognised legally.

During periods where her husband's political career required them to leave their home in Oslo and live in Sweden, she took on representative duties as the spouse of the Prime Minister and hostess at the Norwegian government's residence in Stockholm.