Thurston County Judge Christine Schaller dismissed 14 child pornography charges against Troy Fisher on Monday.
Judge Schaller ruled the evidence found in his case was obtained without a search warrant.
In July of 2012, relatives reported Fisher as missing. Olympia police searched his home, cell phone and computers in an effort to locate him.
When Fisher turned up safe two days later, an Olympia detective continued to search his computer and found the images that resulted the criminal charges.
Fisher was artistic director at Capital Playhouse Theater, a children's music theater, in Olympia.
After the dismissal, Fisher said he wants to resume teaching music.
"I am an innocent man," he said. Fisher explained he never knowingly downloaded any illegal images.
The courtroom was full of parents and former students, all in support of Fisher, who exchanged hugs after the ruling.