Morris was born and raised in Nampa, Idaho, and graduated from Nampa High School in 1993. He was an all-state fullback for the Bulldogs in football and USA TodayAll-American, and also lettered in basketball and track. Morris was also an Eagle Scout and was inducted into the NHS hall of fame in 2010.
In 2000, Morris was selected in the first round (28th overall) of the NFL Draft by the Indianapolis Colts, where he spent his entire career. Morris started at middle linebacker for the Colts for the first 5 years of his career, and was the Colts' leading special teamstackler in the 2006 season. Morris also started 9 games for the Colts during the 2006 season, including 3 games in the playoffs and Super Bowl XLI, replacing Gilbert Gardner to improve the Colts' run defense. In 2001, Morris had his best statistical year with 114 total tackles (84 solo) and one sack. Morris was an unrestricted free agent after the 2006 season concluded and was re-signed by Indianapolis on March 5. He injured his left knee in the fourth game of 2007, and had season-ending surgery. He was released after a failed physical on February 27, 2008.
Morris is an active member of The Church of Jesus Christ of Latter-Day Saints. His ancestry is partly Icelandic, and he grew up in a Mormon family . He served his LDS mission from 1994 to 1996 in Toronto, Canada, and is married with two children.