[3] He was part of the Bahamas' silver medal-winning team in the men's 4 × 400 m relay at the 2008 Beijing Olympics, after running in the heats.

Miller is a former athlete at Dickinson State University where he won nine NAIA track and field national championships in his four-year career.

Miller won a bronze medal at the XIX Commonwealth Games, in Delhi, India.

A year later he won a bronze medal at the 2011 Pan American Games in Guadalajara, Mexico.

He also won gold at the 2012 London Olympics with the Bahamas 4 × 400 m team beating medal favorites USA with a national record.