After completing his tour of duty, he entered Loyola Law School in Los Angeles, finishing near the top of his class and earning his J.D.

After the birth of his children, Michael and Michelle, Harman wanted to spend more time with his family, so he left Lucas & Deukmejian and started his own law firm, which he remained with for 27 years.

Harman's conservative opponent, Dana Point City Councilwoman Diane Harkey, spent $1.2 million of her own money in an attempt to defeat him.

"[citation needed] In June 2006, Harman won 67.8% of the general election vote[1] to be elected to the State Senate to fill the 35th District seat, vacated when John Campbell became a member of the United States House of Representatives.

In this capacity he was chiefly responsible for ensuring the enforcement of proper procedures and rules on the floor of the Senate.