People are the most important pillar of software development process. It is critical to understand how they interact with each other and how these interactions affect the quality of the end product in terms of defects. In this research we propose to include a new set of metrics, a.k.a. social network metrics on issue repositories in predicting defects. Social network metrics on issue repositories has not been used before to predict defect proneness of a software product. To validate our hypotheses we used two datasets, development data of IBM¹ Rational ® Team Concert™ (RTC) and Drupal, to conduct our experiments. The results of the experiments revealed that compared to other set of metrics such as churn metrics using social network metrics on issue repositories either considerably decreases high false alarm rates without compromising the detection rates or considerably increases low prediction rates without compromising low false alarm rates. Therefore we recommend practitioners to collect social network metrics on issue repositories since people related information is a strong indicator of past patterns in a given team.