A strategic lawsuit against public participation ("SLAPP") is a case filed by someone attempting to silence a critical person or group who is exercising their First Amendment rights.
Since 1989, Washington had a decent anti-SLAPP statute, RCW 4.24.510, on the books.
But it just got better with the passage of SB 6395 a few days ago. It awaits the Governor's signature, which should not be a problem.
The bill creates a speedy procedure for a person to test whether a suit is indeed an unlawful SLAPP suit and provides a winning party their attorneys' fees and $10,000. Here is the final bill report summarizing the new law. This should knock out SLAPP suits before they do their intended job: costing people lots in legal costs for merely exercising their First Amendment rights.