Abstract: An example computing system receives annotation data associated with a plurality of customer communication messages is described. The computing system generates, for display on each of a plurality of reviewer computing devices, an annotation interface through which each reviewer may input annotation data associated with an assigned subset of the plurality of messages. The annotation data may include data indicative of whether the message includes a complaint. An annotation process may include receiving annotation data associated with the message from a first reviewer and a second reviewer, and determining whether the annotation data received from the first reviewer and the annotation data received from the second reviewer are in agreement. If not, the annotation process may further include receiving annotation data associated with the message from a third reviewer, wherein the third reviewer has a higher reviewer permission level than both the first and the second reviewer.