After graduating from Ridley, where he won the Mason Gold Medal, Coutts graduated from The University of Western Ontario in 1993. He joined the alternative rock band Our Lady Peace on September 23, 1995, replacing the original bassist, after the band's debut album Naveed was produced. To Our Lady Peace fans, Coutts is known as Duncan. Our Lady Peace has won four Juno Awards and ten MuchMusic Video Awards. Along with the bass, he plays keyboards, cello, and sings back up.