(Seattle, WA)  --  A report from the American Automobile Association says the number of marijuana-related crashes in Washington has risen considerably.  Researchers say the percentage of Washington drivers involved in fatal crashes after recently using pot rose from eight percent in 2013 to about 17 percent in 2014.  Triple-A tells KIRO-TV the figures should serve as a case study for the more than 20 states currently considering legalization of marijuana.  The study also found that, unlike with alcohol, there's no scientific evidence to show people become impaired when they have a specific level of marijuana in their system.