The Democrat was sworn into office by his father William Newsom, who is a retired associate justice of the California Court of Appeal in San Francisco.
Newsom delayed taking over the job in Sacramento so that he could watch over the City's Board of Supervisors appointment of his replacement. He didn't want the person to be from the political far left. After much jockeying, City Administrator Ed Lee, whom Newsom approved of, was selected and is expected to approved officially later this week.
Newsom, known as a political moderate, made a splash on the national stage during his first weeks in office in 2004 when he began to allow same sex couples to marry.
Newsom also left the post with a bang. On Sunday, his final day in office, he surprised just about every one by appointing Chief of Police George Gascon to be the city's new district attorney.
During his first speech as lieutenant governor, Newsom pledged to bring more of California's entrepreneurial spirit to the Capitol. He also pledged to work with Gov. Brown in restoring government.
The lieutenant governor fills in when the governor travels out of state or is incapacitated. Newsom will also serve on the governing boards of the state's public universities and commissions
dealing with economic development and conservation.