Gerrit1 is a modern code review tool that facilitates a traceable code review process for git-based software projects (Bettenburg et al., 2014). It tightly integrates with test automation and code integration tools. Authors upload patches, i.e., collections of proposed changes to a software system,to a Gerrit server.The set of reviewers are either: (1) invited by the author, (2) appointed automatically based on their expertise with the modified system components, or (3) self-selected by broadcasting a review request to a mailing list. Figure 1 shows an example code review in Gerrit that was uploaded on December 1st, 2012. Below, we use this figure to illustrate the role that reviewers and verifiers play in a code review.