William Judson was a 6'1" defensive back out of South Carolina State. He was selected in the eighth round of the 1981 NFL Entry Draft by the Dolphins, 208th overall.
Judson was used sparingly in his first NFL season, appearing in nine Miami games. He totalled three tackles in spot duty as the Dolphins posted a 7-2 record in the strike shortened 1982 season, eventually advancing to Super Bowl XVII, losing to the Washington Redskins 27-17.
In 1983, Judson started all 17 Miami games at left cornerback, including the playoffs. He intercepted six passes, including three against the New York Jets in a week seven 32-14 victory. He finished the season with 82 tackles and eight passes defensed. Miami finished the season 12-4, winning the AFC East before dropping their first playoff matchup, to the Seattle Seahawks, 27-20.
Judson was moved to right cornerback in 1984, a position he would man for the next 90 consecutive (non-replacement player) games. He would record 42 tackles, pick off four passes, knock down 15 more, recover two fumbles and block two field goals. He also picked off Steelers quarterback Mark Malone in the Dolphins 45-28 playoff victory over Pittsburgh. Miami finished the season 14-2, advancing to Super Bowl XIX.
Judson recorded approximately 50 tackles for Miami in 1985, also intercepting four passes. He scored his first career touchdown by returning an interception 61 yards in a week one 26-23 loss to the Houston Oilers. He again displayed his propensity for special teams, blocking both a punt and a field goal. Miami finished 12-4, eventually losing the AFC Championship game to the New England Patriots, 31-14.
1986 would see Judson continue to start every game at right cornerback. He recorded approximately 65 tackles, knocking down 11 passes and picking off two more. The Dolphins finished with an 8-8 record, failing to make the playoffs for the first time since 1980.
In 1987, Judson started all 12 non-replacement player game for the Dolphins. He recorded 44 tackles, defensed nine passes and picked off two more. Miami finished the year 8-7, failing again to qualify for the postseason.
Miami posted a 6-10 record in 1988, as Judson recorded 62 tackles and four interceptions. He also blocked a punt and knocked down 10 passes.
Judson started the first 14 games of the 1989 season, his string broken by an injury late in the season. He collected approximately 60 tackles and made two more picks. The Dolphins again finished 8-8, not enough to qualify for extra football.
Judson spent his entire NFL career as a Miami Dolphin, intercepting 24 passes and scoring two touchdowns on returns.