DARTMOUTH — For the first time in over 100 years, a representative of Bristol County sits on Massachusetts' highest court.

Elspeth "Ellie" Cypher was sworn in Thursday at a ceremony at UMass Dartmouth to the Supreme Judicial Court. The former Bristol County prosecutor, who spent over 16 years on the bench in the state appeals court, was unanimously confirmed to replace retiring Justice Margot Botsford back in March.

Cypher was lauded during the ceremony by Lt. Governor Karyn Polito and Governor Charlie Baker for her work ethic and her ability to put herself in other people's shoes. Cypher said it's important to contribute as much as possible to society.

"We must avoid the danger of futility," Cypher said, "By understanding that one person can make a difference. Our destiny will be determined not by government alone, but by individual role, personal responsibility and responsible citizenship."

Lt. Governor Polito pointed to Cypher's ability to write 1000 appellate decisions while also serving as author and editor of state criminal procedure and law, working as a professor, a mother and a spouse, as an indication to the type of hard worker she is.

"Amazing work ethic," Polito said. "Some might want to describe her as a work horse, not a show horse."

Polito also said, "100 years is now behind us," referencing the fact that Cypher is the first justice on the state's highest court to come from Bristol County in more than a century.

Governor Charlie Baker applauded Cypher's ability to put herself in other's shoes to better understand what they have to endure. He recalled Cypher's 10 years spent working on the state's case against James Kater, the man eventually convicted of killing 15-year-old Mary Lou Arruda in 1978 in one of Massachusetts' most grisly crimes. Cypher was part of three of Kater's four trials in the killing of Arruda, and Baker said she was a tireless advocate for Arruda's family getting justice.

"And do so not just with vigor, but with imagination, intelligence and creativity within the bounds of the law, to find the path that would ultimately result in what most people believe was the right result," Baker said.

Cypher lives in Assonet with her wife, Sharon Levesque, and their son, Austin.