The Washington state Supreme Court says three "faithless" electors who bucked a pledge to vote for the Democratic Party's presidential nominee and failed to cast their Electoral College votes for Hillary Clinton in 2016 can be fined $1,000 each as required by state law.

The state high court ruled 8-1 on Thursday the three electors who challenged the penalties could be fined because they opted not to vote for Clinton and her running mate, Tim Kaine, during the 2016 presidential election and instead voted for former Secretary of State Colin Powell for president. A fourth elector not named in the lawsuit voted for Faith Spotted Eagle, a Native American activist fighting the Keystone XL Pipeline.

Election law in Washington requires electors to pledge to vote for the candidate of their respective political parties or face a fine of up to $1,000. Because Clinton and Kaine won the popular vote in Washington, the state’s electors were required by the pledge to support Clinton.

But with Donald Trump on the brink of besting Clinton for the presidency, some electors, including the four from Washington, decided not to vote for either candidate in an effort to block Trump from receiving the Electoral College votes needed to become president. If Trump failed to secure the majority of Electoral College votes, the House of Representatives would decide who took the White House.

As a result of their decision to vote for candidates other than Clinton, the electors were fined $1,000 apiece.

The three contested the penalties on the grounds they were unconstitutional. Electors, they argued, are supposed to exercise independent judgment when casting their ballots, and imposition of the fines under state law interferes with the federal electoral process.

A judge on the Thurston County Superior Court, however, upheld the fines. The Washington state Supreme Court agreed with the lower court's ruling.

“The power of electors to vote comes from the state, and the elector has no personal right to that role,” the court said.

The Constitution, the court added, grants the states “plenary power to direct the manner and mode of appointment of electors to the Electoral College,” and the penalty imposed under state law “falls within that authority.”

Faithless electors have popped up occasionally, but the 2016 presidential race gave them a new prominence. In addition to the four in Washington that went to the Democratic ticket, another elector pledged to Hillary Clinton in Hawaii didn't vote for her, instead backing Sen. Bernie Sanders, I-Vt., for president and Sen. Elizabeth Warren, D-Mass., for vice president.

On the Republican side, two Texas electors for Trump bolted, backing then-Ohio Gov. John Kasich and former Rep. Ron Paul of Texas.