In 1981, at age thirteen, Alioto-pier was paralyzed from the waist down when she fell from a ski lift in the Lake Tahoe area. Alioto-Pier later received a degree in anthropology from UCLA.
Early political career
After working as an aide to Vice President Al Gore, Alioto-Pier made her first run for public office at 28 in 1996 against Republican Congressman Frank Riggs in California's 1st congressional district, which included Napa, Mendocino, and Humboldt counties, stretching along the coast up to the Oregon border. She won the Democratic nomination, but lost the general election. She is credited with mounting a strong campaign despite the loss. At the time, she ran under the name Michela Alioto. Shortly after losing that election, Alioto-Pier announced that she would try again in 1998 but withdrew from the race in deference to fellow Democrat Mike Thompson. Instead, she ran for the office of California Secretary of State and won the Democratic nomination but ultimately lost against Republican incumbent Bill Jones. She again ran for Secretary of State in 2002, but lost the Democratic nomination to fellow San FranciscanKevin Shelley, whose father preceded Alioto-Pier's grandfather as that city's mayor.
San Francisco Board of Supervisors
In January 2004, Alioto-Pier was appointed by Mayor Gavin Newsom, to his old seat in District 2 on the San Francisco Board of Supervisors. Although even numbered districts were not slated for an election until 2006, an off-year election was held for District 2 because she was an appointed supervisor. Alioto-Pier ran for the seat in the November 2004 election and won, and in 2006 she ran for reelection and easily won the seat. As a Supervisor, Alioto-Pier is committed to the preservation of St. Brigid's Church, which was once slated for demolition. Another top priority for Alioto-Pier is earthquake preparedness, especially important for her district, hit hard by the 1989 Loma Prieta earthquake. Alioto-Pier explains:
As the district representative for a community that was really hit in Loma Prieta, It is my responsibility to make sure if something like that happens again that we know what we're doing.
As a San Francisco moderate, Alioto-Pier has been attacked by San Francisco progressives for having a poor attendance record and mediocre constituent relations. One significant source of the criticism is over Alioto-Pier's attendance record while she was giving birth to her third child, which was a first for an elected official in San Francisco. Alioto-Pier responded by passing a family leave policy for elected officials in San Francisco. On July 20, 2009, San Francisco Chronicle political columnists Phillip Matier and Andrew Ross broke the story of Alioto-Pier's announcement for state insurance commissioner. Alioto-Pier subsequently left the race for Insurance Commissioner due to a leg injury.
Re-election challenge in 2010
On June 3, 2010, Alioto-Pier submitted papers to register as a candidate for re-election to District Two of the San Francisco Board of Supervisors. San Francisco Department of Elections Director John Arntz issued a letter that same day in which he announced she was ineligible to run for re-election for District Two supervisor due to a 2008 ruling regarding term limits issued by City Attorney Dennis Herrera. Arntz wrote, "Accordingly, the Department of Elections cannot list you as a candidate for this office on the November 2, 2010 ballot or any other election materials for that election." She would have served on the Board of Supervisors for seven years when her term expired in January 2011. Supervisors are limited to serving two four-year terms. The municipal ordinance providing for term limits was a matter of debate. Some claimed that the ordinance states that any person who has served more than one-and-a-half four-year terms in office shall be deemed to have effectively served for two full terms and thus be ineligible to seek re-election. Others claimed that the law is more nuanced and that one must be appointed to serve more than two years for it to count as a full term. Alioto-Pier was appointed to serve one year, ran for a two-year term, and then ran again for a four-year term. According to this view, the question is whether or not the year she served as an appointed supervisor and the truncated two years she served can be combined and rounded up to count as a four-year term. Alioto-Pier challenged the ruling from the Department of Elections in Superior Court and won. In response, City Attorney Dennis Herrera, appealed that decision and overturned her victory, forcing her out of the 2010 election for District 2 Supervisor.