[2] On October 20, 1979, Bates recorded 8 tackles, a sack, and 2 fumble recoveries against Alabama, who were ranked number one and would go on to win the national championship that year.
During Tennessee's 16–15 loss to eventual national champion Georgia on September 6, 1980, Georgia running back Herschel Walker and Bates met on the 5-yard line in a play that still lives in many college football highlights.
He was selected by the New Jersey Generals in the 1983 USFL Territorial Draft, but he decided to sign as an undrafted free agent with the Dallas Cowboys, which had been his favorite team growing up.
He started in the regular-season against the Seattle Seahawks in the playoffs against the Los Angeles Rams at strong safety, replacing an injured Dextor Clinkscale.
In 1984, he missed 4 games after being placed on the injured reserve list, because of a preseason injury suffered against the Green Bay Packers.
He started against the Indianapolis Colts at strong safety, making a team-high 7 tackles, one sack, one interception, one pass defensed and one fumble recovery.
He was selected to the Pro Bowl in just his second year, after influencing the NFL to create a first-time roster spot for special teams players that were non-returners, making Bates the first such player to receive that honor.
At the end of the 1989 season, Jimmy Johnson informed Bates that he was going to be left unprotected on the team's Plan B free agency list.
This award is selected by a vote of the fans and annually goes to the Cowboy player who displays leadership and character on and off the field.
He was on injured reserve during the 1992 season, when the Cowboys played in Super Bowl XXVII, due to a knee injury.
Tom Landry once said, “If we had 11 players on the field who played as hard as Bill Bates does and did their homework like he does, we’d be almost impossible to beat”.
[7] He described Bates (Real Kill) and Cliff Harris (Captain Crash) as "the hardest hitters I ever saw.
"[8] Referring to Bates' reputation as a hard hitter, John Madden stated, "Every game starts with a kick.