Coady attended J. J. Pearce High School in Richardson, Texas and was a student and a letterman in football and basketball.
As a senior Coady was First-team All-Big 12 and made 86 tackles (57 solo) and had three interceptions.
His stock rose quickly in the draft due to his workout at the NFL Combine where he tested with a 4.55 40-yard dash, 20 reps of 225 lb (102 kg).
On August 30, 2002, the Tennessee Titans claimed Coady and signed him to a one-year $890,000 contract.
In the training camp of 2003 the Rams had several injuries at the safety position and Coady was familiar with their system so on August 30, 2003, the Rams traded a conditional seventh-round draft pick to the Colts for Coady, less than six months after signing him as an unrestricted free agent.
Coady was signed by the Atlanta Falcons on March 7, 2005, but was subsequently cut in August 2005.