Patrick Olmstead (plaintiff) purchased a DVD player from Pioneer Electronics (USA), Inc. (Pioneer) (defendant). Olmstead claimed that the DVD player was defective. Olmstead sued Pioneer on his own behalf and on behalf of a class of consumers who purchased the same model of DVD player. Through discovery, Olmstead ask Pioneer for information about other complaints Pioneer had received about the DVD player. Pioneer gave Olmstead 700 to 800 complaints, but Pioneer also redacted the names and contact information of the consumers who had submitted the complaints from the documents it gave to Olmstead. Olmstead filed a motion to compel Pioneer to give him the names and contact information of these other complainants. Pioneer asserted that disclosing this information would be a violation of the other complainants’ right to privacy under the California constitution. The trial court granted the motion to compel and ordered Pioneer to notify each of the complainants that their information would be disclosed unless they objected. Pioneer appealed. The California Court of Appeal reversed, holding that the California constitution required each of the complainants to affirmatively consent to the disclosure of their information. Olmstead petitioned the California Supreme Court for review.