The government's case includes evidence that Vick and his cohorts "tested" pit bulls for ferocity. If the dogs failed the test, the indictment charges, they were executed by hanging or drowning. In one case, with Vick present, the indictment says a dog was slammed to the ground until it was dead. In another incident, a dog was soaked with a hose, then electrocuted.

One source close to Vick, who I talked to this spring for the story I wrote about the Falcons quarterback's recent slide from grace in Atlanta, gave me a rather blunt rationale for Vick's involvement in dog fighting:

"He's not very bright at all,'' the source said of Vick. "And that's a big part of his problems. He's a very unintelligent person and he makes poor decisions because of it. It's not a white or black thing. Paris Hilton is an idiot, too. Mike Tyson was totally dumb, but for a long time his trainer kept him protected from his worst mistakes. You have to have someone around you who can protect you from yourself at times.''

Another league source I talked to had a slightly different take. He too watched Vick up close for years and came to this conclusion:

"I've seen what he's truly about, and now, the rest of the world sees what he's truly about,'' the source said. "He's not dumb, and he's not a bad guy. He's just selfish. He's an extremely selfish human being. He doesn't care about his team or his teammates. He says he does, but he doesn't.''

Harsh words to be sure. But these are some of the same sources who, more than two months ago, assured me Vick -- despite his proclamation of innocence -- was heavily involved in the dog-fighting operation in Virginia, from its earliest stages on. With Tuesday's indictments becoming public, the assessment of those sources has been echoed by federal investigators and a grand jury.

ATLANTA -- In what has quickly evolved into a collaborative effort that includes the input of officials from the NFL, the NFL Players Association and the Atlanta Falcons, embattled quarterback Michael Vick could be urged to take a voluntary leave of absence to focus his energy on the legal challenges from a federal dogfighting indictment confronting him, sources said Thursday and Friday.

ATLANTA - While commissioner Roger Goodell was meeting with officials of the ASPCA, about 50 people urged the NFL to “Sack Vick” Friday in a demonstration outside the league’s headquarters following the indictment of Michael Vick on dogfighting charges.

“Sack Vick!” chanted the demonstrators, organized by People for the Ethical Treatment of Animals as they walked peacefully in front of the Park Avenue building. Many held dogs who had the “Sack Vick” signs on their backs and one woman brought a pit bull, the breed killed in the dogfighting operation the Atlanta quarterback is accused of sponsoring.

The leaders of the demonstration focused on Goodell’s one-year suspension of Tennessee’s Adam “Pacman” Jones under the NFL’s personal conduct policy, although Jones has not been convicted of any crime.

“We think they should do the same with Michael Vick,” said Dan Shannon, an assistant director of campaigns for PETA. “We don’t think their ’wait and see’ attitude goes far enough. If they suspended Pacman Jones, they can suspend Vick.”

The NFL said after Vick was indicted Tuesday, it was watching legal developments in the case. Vick is scheduled to be arraigned Thursday in federal court in Richmond, Va.

“Michael Vick’s guilt has not yet been proven, and we believe that all concerned should allow the legal process to determine the facts,” the league’s statement said. “The matter will be reviewed under the League’s Personal Conduct Policy.”

On Friday, an NFL spokesman addressed the protest.

“We agree with them that dogfighting is cruel, degrading and illegal,” Brian McCarthy said. “The alleged activities are very disturbing and we are extremely disappointed Michael Vick has put himself in this position.

“We are having extensive dialogue with numerous groups and individuals, including the ASPCA, and are reviewing all of our options to deal with this as quickly as possible.”

Sherry Ramsey, a staff attorney for the Humane Society of the United States, said she was disappointed at the league “wait and see attitude.

“There is a precedent in the Jones suspension,” she said.

Ramsey said her organization wrote to the NFL in May, offering to work with the league to help educate players about dogfighting. She said it did not receive a reply.

However, two letters written June 21 by the NFL to the Humane Society, provided to The Associated Press by the league, said warnings on animal fighting and animal cruelty are now being included in the annual briefings by the league security staff to players. Those briefings will take place at all 32 training camps this summer.

“We are in total agreement that there is no place for animal cruelty and illegal animal fighting and take very seriously the allegations of dog fighting against Michael Vick,” Peter Abitante, Goodell’s personal assistant, wrote nearly a month before Vick’s indictment.

“We certainly do not condone this activity and will not tolerate cruelty or mistreatment of animals. If Mr. Vick or anyone associated with the NFL is found to have violated state or federal law, the commissioner has stated publicly that he will impose significant discipline under our personal conduct policy.”

Earlier this year, the NFL began working with the American Society for the Prevention of Cruelty to Animals on programs and public service announcements to educate players and the public on the importance of caring properly for animals.