The state Supreme Court on Thursday overturned the conviction of a man who was arrested on drug charges because the officer who saw the alleged crime was not the arresting officer.

Under state law, unless a specific statutory exception applies, only an officer who is present during the offense may arrest a suspect for a misdemeanor or a gross misdemeanor. Exemptions include traffic infractions where an officer can ask another to arrest the driver.

Gregorio Ortega was arrested in March 2009 in Seattle after an officer on the second floor of a building observed Ortega and another man purportedly appear to make three drug transactions. The officer in the building maintained radio contact with officers in a car nearby, described Ortega's activities and instructed them to arrest him. The officers found crack cocaine and cash on him, the court wrote.

In a unanimous ruling, the court reversed a Court of Appeals ruling in 2011 that upheld his 2009 conviction of possession of cocaine with intent to deliver, because it said the circumstances of his arrest went against state law.