Referee Jack Vest, the referee for Super Bowl II, the 1969 AFL championship game and 1971 AFC championship game, was killed in a June motorcycle accident. Chuck Heberling was promoted from line judge to fill the vacancy and kept Vest's crew intact. Heberling's line judge vacancy was filled by Red Cashion, who was promoted to referee in 1976 and worked in the league through 1996, earning assignment to Super Bowl XX and Super Bowl XXX.
Major rule changes
The inbounds lines or hashmarks were moved 10.75 ft (3.28 m) closer to the center of the field, to 70.75 ft (21.56 m) from the sidelines. Since the 1945 season, they had been 20 yd (18.29 m) from the sideline [40 ft (12.19 m) apart]. The hashmarks are now 18.5 ft (5.64 m) apart (the same width as the goalposts), cutting down on severe angles for short field goal attempts, and nearly eliminating the short-side fields for the offense.
With the hashmarks now the same width as the goalposts, a team punting from inside its 15-yard line could snap the ball from a spot even with the marked field numbers instead of the hashmarks to avoid the punt hitting the goalpost.
Field number markings were standardized across the league, both in size and position.
The fields for the Houston Oilers and New Orleans Saints had field numbers closer to the sidelines than most stadiums, since they were marked with both NFL and collegiate hashmarks.
Yard lines ending in "5" could not be marked. In 1971, the Buffalo Bills and New York Giants were the last teams to mark yard lines every five yards instead of ten.
If a legal receiver goes out of bounds, either accidentally or forced out, and returns to touch or catch the pass in bounds, the penalty is a loss of down (but no penalty yardage will be assessed).
If a punt or missed field goal crosses the receivers' goal line, a member of the receiving team may advance the ball into the field of play. Previously, the ball was dead when a scrimmage kick crossed the goal line and the receivers were awarded an automatic touchback.
All fouls committed by the offensive team behind the line of scrimmage will be assessed from the previous spot.
Tie games, previously ignored in computing of winning percentage, were made equal to a half-game win and a half-game loss.
This was the first season third-down conversions were recorded as an official statistic.
From 1970 through 2002, there were three divisions (East, Central and West) in each conference. The winners of each division, and a fourth "wild card" team based on the best non-division winner, qualified for the playoffs. The tiebreaker rules were changed to start with head-to-head competition, followed by division records, common opponents records, and conference play.
Note: Prior to the 1975 season, the home teams in the playoffs were decided based on a yearly rotation. Had the playoffs been seeded, the divisional matchups in the AFC would not have changed, but undefeated Miami would have had home field advantage for the AFC championship game. The NFC divisional matchups would have been #4 wild card Dallas, ineligible to play Washington, at #2 Green Bay and #3 San Francisco at #1 Washington.
Buffalo Bills: After finishing with a 1–13 record in 1971, Harvey Johnson was reassigned to the team's scouting department. Lou Saban then was named as Johnson's replacement, beginning his second stint after serving as the Bills head coach from 1962 to 1965.
The Houston Oilers switched from silver to blue helmets. They also discontinued their silver pants in favor of white pants for their blue jerseys, and blue pants for their white jerseys. These uniforms lasted three seasons.
The Miami Dolphins reinstated their white jersey with alternating aqua and orange stripes on the sleeves, which was discontinued when Don Shula became coach. However, this style was not universally adopted, and several notable players, including Bob Griese and Larry Csonka, continued to wear the 1970-71 white jersey with plain sleeves. The Dolphins' aqua jerseys from 1970-71 with plain sleeves, worn twice in 1972 (vs. Buffalo in week 6 and St. Louis in week 11), remained unchanged.
The Washington Redskins switched from gold to burgundy helmets, and from the "R" helmet logo (designed by the late Vince Lombardi) to the Native American head logo. The helmet remained unchanged, save for changing from gray face masks to gold in 1978 and a modified logo for 1982 only, until the Redskins nickname was retired prior to the 2020 season.
^100 Things Braves Fans Should Know and Do Before They Die: Revised and Updated, Jack Wilkinson, Triumph Books, Chicago, 2019, ISBN 978-1-62937-694-3, p.3