Jones specialized in quarterback "sacks", a term which he coined. Nicknamed "the Secretary of Defense", Jones is considered one of the greatest defensive players ever. The Los Angeles Times called Jones "Most Valuable Ram of All Time," and former Redskins head coach George Allen called him the "Greatest Defensive End of Modern Football".
When he was 14 years old, he witnessed a carload of white teenagers laughingly hit an elderly black church woman with a watermelon. The woman died days later from the injury, and there was never a police investigation. "Unlike many black people then, I was determined not to be what society said I was," Jones later recounted. "Thank God I had the ability to play a violent game like football. It gave me an outlet for the anger in my heart."
South Carolina State revoked Jones' scholarship after they learned that he was a part of a civil rights protest. However, one of the assistant football coaches at South Carolina State was leaving to coach at Mississippi Vocational, and told Jones and some of the other African American players that he could get them scholarships at the new school. While he was playing at Mississippi Vocational, he and his African American teammates had to sleep in cots in the opposing team's gym because motels would not take them on numerous occasions.
"I'm probably the toughest (expletive) here. Ain't no
question about that with me. I'm the toughest guy
here... I'm clean. I mean, I ain't got no marks on
me. I don't know nobody else who can say that
who came out of any sport. I ain't got no marks on
me, so I've got to be the baddest dude I know of."
Jones won consensus All-Pro honors five straight years from 1965 through 1969 and was second-team All-Pro in 1964, 1970, and 1972. He was also in seven straight Pro Bowls, from 1964 to 1970, and was selected to an eighth after the 1972 season with the San Diego Chargers. He was voted the team's Outstanding Defensive Lineman by the Los Angeles Rams Alumni in 1962, '64, '65, and '66. In 1971, Jones suffered a severely sprained arch, which caused him to miss four starts, and he ended the season with 4½ sacks, his career-low to that point.
In 1972, Jones was included in a multiplayer trade with the San Diego Chargers, where he was an instant success. He was named San Diego's defensive captain and led all Chargers' defensive linemen in tackles and won a berth on the AFC Pro Bowl squad. He concluded his career with the Washington Redskins in 1974. In the final game of his NFL career, the Redskins allowed him to kick the point-after-touchdown for the game's last score. Along the way, Jones was named the Associated Press NFL Defensive Player of the Week four times: week 14, 1967; week 12, 1968; week 11, 1969; and week 10, 1970.
An extremely durable player, Jones missed only six games of a possible 196 regular-season encounters in his 14 National Football League seasons.
Jones was considered by many to revolutionize the position of defensive end. He was credited with coining the phrase "sacking the quarterback". In 1999, Jones provided an L.A. Times reporter with some detailed imagery about his forte: “You take all the offensive linemen and put them in a burlap bag, and then you take a baseball bat and beat on the bag. You’re sacking them, you’re bagging them. And that’s what you’re doing with a quarterback.”
What separated Jones from every other defensive end was his speed and his ability to make tackles from sideline to sideline, which was unheard of in his time. He also was the first pass rusher to use the head slap, a move that he said was, "...to give myself an initial head start on the pass rush, in other words an extra step. Because anytime you go upside a man's head … or a woman; they may have a tendency to blink they [sic] eyes or close they eyes. And that's all I needed. " “The head slap was not my invention, but Rembrandt, of course, did not invent painting. The quickness of my hands and the length of my arms, it was perfect for me. It was the greatest thing I ever did, and when I left the game, they outlawed it.”
Pro Football Weekly reported he accumulated 173½ sacks over his career, which would be third on the all-time sack list. (Jones would have ranked first all-time at the time of his retirement, and since has been surpassed by two fellow Hall of Famers Bruce Smith and Reggie White.) 
In 1967, Jones had 21½ sacks in only 14 games, which (if official) would stand as the single-season record. (The term "sack" had not yet been coined at the time, and official sack statistics were not recorded by the NFL until 1982.) Then in 1968, Jones tallied 22 sacks in 14 games, also more than the current NFL record.
Jones worked as a television actor, and appeared in numerous TV programs since the 1970s, most often appearing in cameo roles. He appeared in an episode of The Odd Couple where he and Oscar were in a television commercial selling shaving products. He appeared on The Brady Bunch, and in a Bewitched episode in 1969, he played a guard to the Giant's castle in "Jack & the Beanstalk". Jones also played himself on an episode of Wonder Woman in 1978.
In 1978, he played a Viking named 'Thall' in The Norseman. Fellow Hall of Famer Fred Biletnikoff joined Jones in that film, also portraying a Norseman. That same year, Jones portrayed a fierce defensive lineman named 'Gorman' in the film Heaven Can Wait.
In the series G vs E, he played himself, but as an agent of "The Corps". He also played a role in the hit show, ALF, where he played a father figure to Alf.
NFL.com reported that Jones made several trips to Iraq to visit the U. S. military.
Jones served as the president and CEO of the Deacon Jones Foundation, an organization he founded in 1997 "to assist young people and the communities in which they live with a comprehensive program that includes education, mentoring, corporate internship, and community service."
Jones was one of the many former L.A. Rams players who disliked the team's controversial relocation to St. Louis in 1995. He was adamant in interviews and appearances to state that he played for Los Angeles, not St. Louis, and considered the Rams franchise there a different team that should have a different name, leaving the Rams name for L.A. He participated in many grassroots efforts to bring NFL football back to L.A. and also voiced support on many of the new stadium proposals .
Jones has stated that he gave himself the nickname Deacon after joining the Rams because too many David Joneses were in the local phone book. "Football is a violent world and Deacon has a religious connotation," he told the Los Angeles Times in 1980. "I thought a name like that would be remembered."
Deacon Jones's wife Elizabeth is the chief operating and financial officer of the Deacon Jones Foundation, based in Anaheim Hills, California., the community in which the couple lived.