She graduated from Occidental College with a Bachelor of Arts degree in 1972 and later from Notre Dame Law School with a Juris Doctor in 1975.

Sammartino was a judge on the San Diego Municipal Court from 1994 to 1995.

She was a judge on the San Diego County Superior Court from 1995 to 2007.

[2] Sammartino was nominated to the United States District Court for the Southern District of California by President George W. Bush on March 19, 2007, to a seat vacated by the death of Judge Judith Keep.

[2] On May 17, 2017, Sammartino sentenced Rear Admiral Robert Gilbeau, the first active duty admiral ever convicted of a felony, to 18 months in prison for his involvement in the Fat Leonard scandal, although Gilbeau will still be allowed to continue collecting his nearly $10,000 monthly pension.