(CNN) -- Football Commissioner Roger Goodell upheld suspensions for four current and former New Orleans Saints players accused of taking part in a three-year "bounty" program, but he reduced the terms for two former team members, the NFL announced Tuesday.
Former Saints defensive lineman Scott Fujita's three-game suspension was cut to one game, while the eight-game penalty given to Anthony Hargrove was cut to seven. But the two who remain with the Saints -- Will Smith and Jonathan Vilma -- saw no change to their suspensions, the league announced.
NFL officials have concluded all four helped lead a program that offered bonuses to Saints players who inflicted injuries on opponents over a three-year period. Goodell found the program "represented conduct detrimental to the league and professional football."
"Our investigation disclosed nearly two dozen players who either contributed to, or received money from, the pool operated by the Saints' defense. The four disciplined players either were involved in specific bounties on an opposing player, contributed substantially to the bounty program, engaged in payments that violated League rules or were untruthful when the program was initially investigated," Goodell said.
The NFL already has penalized the Saints and members of its coaching staff of the program, which operated from 2009-2011. The NFL Players Association, the player's union, said it would "thoroughly" review Goodell's decision "and review all options to protect our players' rights with vigilance."
"For more than six months, the NFL has ignored the facts, abused the process outlined in our collective bargaining agreement and failed to produce evidence that the players intended to injure anyone, ever. The only evidence that exists is the League's gross violation of fair due process, transparency and impartiality during this process."
But in letters to the players, parts of which were released by the NFL, Goodell wrote that he believes all four deserved suspensions.
Vilma, a Saints defensive captain, drew the longest suspension of the four. He was ordered to sit out a full season and is currently on the Saints' injured reserve list. In a letter announcing his decision, Goodell said he's convinced Vilma pledged $10,000 to any teammate who could hurt then-Minnesota Vikings quarterback Brett Favre "to an extent that he would not be able to continue playing" in the 2009 National Conference playoffs.
"I recognize that you and some of your teammates have denied that you made such a pledge or claim not to recall your doing so, but I am persuaded, based on the entirety of the record before me, that you did so," Goodell wrote. "And I find that such a pledge or any similar incentive is conduct detrimental."
Goodell said Smith, who has been on the field for the Saints this season, acknowledged that he approved of the program but denied "that anyone intended to inflict injury on any opposing player."
"Even in the face of repeated appeals to 'crank up the John Deere tractor and cart the guy off,' you and others now claim that the objective was instead merely to 'knock the wind out' of your opponents, requiring them to leave the game for only a play or two," he wrote. "From the standpoint of player safety, fair competition and the integrity of the game, the issues with which I am concerned today, this kind of after-the-fact explanation is little more than wordplay that, in my judgment as Commissioner, offers no basis on which to excuse conduct that does not belong in professional football."
As for Fujita, now with the Cleveland Browns, Goodell said he had no evidence that the player had contributed to the bounty pool, but knew about it and didn't speak out against it.
"Your failure to act contributed to allowing this program to remain in place not only during the 2009 season, but for two additional seasons after that," Goodeel wrote.
Meanwhile, Hargrove is now a free agent and will be credited with the five regular-season games he has missed so far -- leaving him to sit out two games once he's signed to another team. Goodell wrote that Hargrove tried to mislead investigators and block the NFL probe into the Saints and made several statements that were "not credible" during a mid-September meeting.
CNN's David Close contributed to this report.