"On the court, I was able to make a difference to more people," he wrote in an email to The Associated Press last year.
The retired 70-year-old jurist passed away Wednesday night of mouth and throat cancer, said one of his daughters, Jolie Lofink. Chambers, who wrote important opinions about the state's foster care system and the right to an attorney, blamed the illness on his 20-year nightly cigar habit.
Chambers was born and raised in the Yakima Valley, and grew up working on cars in his father's gas station, according to biographical information supplied by family friend Lori Haskell.
He graduated from Washington State University and from the University of Washington School of Law, then spent three decades in private practice before being elected to the court in 2000. He also served as president of the state bar association.
He was a successful trial lawyer who sued over product and highway safety issues, and he helped win money for nursing home residents who sought to return to their own homes.
"Being a lawyer has afforded me many opportunities to make a difference and I have had a very, very rewarding career," he wrote. "I represented real people caught in the grip of the law, usually through no fault of their own."
He kept a blog on his website, www.tomchambers.com, in which he lent insight into what it was like to be a justice. When he was elected in 2000, he wrote: "I am elected to the Washington Supreme Court, the state's highest court. Pinch me. Only in America could all of this happen to a kid raised behind a gas station."
One of his most important opinions came in Braam v. State, when he wrote for a unanimous court that children in Washington's foster care system have a constitutional right to be free from unreasonable risks of harm. He was moved, he told the AP, by the story of one of the plaintiffs, a girl who graduated from high school with a 3.5 grade-point average despite having been moved 22 times in seven years.
The ruling - the first such holding by a state supreme court in the U.S. - prompted a settlement in which Washington agreed to fix its foster care system.
Another opinion, in 2010, ordered a new trial for a Grant County boy convicted at age 12 of sexually molesting a young neighbor. Chambers wrote that the boy's vastly overworked public defender failed to investigate his case.
The boy was eventually exonerated, and the ruling paved the way for the court to adopt new standards for how many cases public defenders can handle.
As Chambers fought cancer, doctors had to remove half his tongue early last year. It was his fourth cancer surgery, and the first time he missed oral arguments.
When he returned to the bench, he had a trachea hole in his throat. When he wanted to ask lawyers a question, he would send it to another justice by instant message.
He underwent radiation and chemotherapy in spring 2012 and attended oral arguments throughout June from his home in Issaquah. He donned his black robe as he appeared in the courtroom via Skype, and said he was touched by how the other justices rallied to help him and allow him to participate.
He said he had long intended to step down at the end of 2012, and the decision did not have to do with his health. He had planned to travel in his retirement: the Kentucky Derby, JazzFest in New Orleans, and Cuba were all on his list.
He was able to do some traveling in the past year, Lofink said.
Chambers is survived by Judy, his wife of 46 years; three children, including Lofink, daughter Jana Jiwani and son Tom Chambers Jr.; and six grandchildren.
A public memorial is planned Jan. 9 at the Museum of Flight in Seattle.