Shannon Patricia Elizabeth O'Brien (born April 30, 1959) is an American politician and attorney who served in the Massachusetts House of Representatives from 1987 through 1993, in the Massachusetts Senate from 1993 through 1995, and was the Massachusetts state treasurer from 1999 through 2003. In that last position she became the first woman to be elected in Massachusetts to statewide office by her own accord. She was the Democratic Party nominee in the 2002 Massachusetts gubernatorial election, but lost in the general election to Mitt Romney.

Early life and education

Four generations of O'Brien's family have served in elected office in Massachusetts government. Her great-grandfather, Michael T. O'Brien, was the proprietor of the family funeral home in Easthampton, Massachusetts, and first elected to the state legislature in 1930.

Shannon's mother is named Ann. Shannon has four siblings:

O'Brien was born in Boston, Massachusetts. She graduated from Yale University in 1981, where she was captain of the Yale Bulldogs varsity women's soccer team. She received her Juris Doctor degree from the Boston University School of Law in 1985.

Career

Politics

thumb|left|O'Brien as a State Representative in 1987

O'Brien worked for a large Boston law firm before her father alerted her to an open seat in the state legislature, which she won. she forced public disclosure of a $2 billion cost overrun.

In January 2014 OIKOS Software appointed O'Brien to its board of directors.

In August 2022, State Treasurer and Receiver General Deb Goldberg appointed O'Brien as Chair of the Cannabis Control Commission. Goldberg suspended O'Brien from the position on September 15, 2023.

She was fired a year later after Goldberg found credible allegations of racial insensitivity and bullying. On September 2, 2025, Judge Robert Gordon of the Suffolk County Superior Court ruled that Goldberg's decision failed to meet the "high bar for removal" and ordered that O'Brien be reinstated with back pay.

Personal life

O'Brien lives in Massachusetts with her husband, former state representative Emmet Hayes, and children.

Electoral history

  • 2002 election for Governor
  • Mitt Romney (R), 49.8%
  • Shannon O'Brien (D), 44.9%
  • Jill Stein (G), 3.5%
  • Carla Howell (L), 1.1%
  • Barbara Johnson (I), 0.7%

References

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