The dogfights on Michael Vick's property followed very strict rules, authorities say.

Weighing in just half a pound too much or too little disqualified dogs from matches.

AP (ENLARGE)

Federal and state authorities search Vick-owned property on July 6.

AP (ENLARGE)

A dog removed from the Vick property during a previous search in May.

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Dogs were bathed immediately before fights to make sure their coats were not "tainted" with a drug or poison that might hinder an opponent. Sometimes they were starved to make them more vicious in the pit.

For owners and carefully screened spectators, these fights sometimes offered purses worth thousands of dollars.

For the dogs, losing could lead to a gruesome execution.

This is how federal prosecutors describe a large dogfighting operation that they say operated out of Vick's 15-acre property in Surry County, Va. They have filed no charges. And Vick, the Atlanta Falcons' quarterback and one of the highest-paid players in the National Football League, has denied any involvement in dogfighting. His lawyer did not respond Friday to a request for an interview.

Regardless, by giving such a detailed account in court documents, prosecutors are sending strong signals about their investigation's focus. They say the dogfighting organization, known as Bad Newz Kennels, violated federal law by sponsoring or otherwise taking part in fights for which animals were transported across state lines.

Federal authorities in Virginia declined to comment this week.

The documents, filed in U.S. District Court in Richmond, do not name Vick or anyone else. Nor do they say how authorities learned the details of a typical fight night at Vick's property. But the specificity with which they describe the culture of dogfighting, particularly as it allegedly took place on Vick's property within a year after he purchased it in 2001, suggests that one or more informants guided investigators on two recent raids.

"They got good, solid evidence from somewhere, either an informant or a psychic," said John Goodwin of the Humane Society of the United States. "Someone is providing very accurate information."

Surry County officials may present the case to a local grand jury on July 24. They have sent mixed signals on whether they have enough evidence to file charges.

But federal authorities appear to be taking control of the investigation, which began when local police searched Vick's property after his cousin, who lived there, was arrested on drug charges.

On a judge's orders, U.S. marshals last week took custody of the 53 dogs that local authorities seized from Vick's property in April. Many of those dogs, court records say, had scars or injuries that appeared to come from organized fights.

Prosecutors are asking a judge to force the dogs' owners to forfeit their ownership of the animals, since they are considered the gains from illegal activity. If Vick wants to stake claim to any of the animals, he'll have to file a notice in federal court by September.

"The dogs are currently being cared for at facilities in the Eastern District of Virginia," Jim Rybicki, a spokesman for the U.S. attorney in Alexandria, Va., said by email Friday. "However, they remain under U.S. government custody. They will continue to be held in government custody until the court adjudicates the forfeiture action."

Along with the dogs, authorities seized performance-enhancing drugs that, court records say, were used to make dogs fight better or to help injured animals fight longer. They found equipment associated with dog fighting operations, including a "rape stand" used in forced breeding, a digital scale used to weigh dogs before fights, and a fighting pit, stained in blood.

Authorities also confiscated two handguns; court records say some dogs have been shot to death after fights.

Despite the illicit nature of the enterprise, the fights operated under a strict code, court records indicate.

The two dogs entered in each fight had to be the same gender and weight. Participants would agree on a fighting weight in advance, and each dog had to weigh within a half-pound of that mark. Any greater deviation would result in a dog being scratched from the fight; its owner might have to pay the opponent's owner to make up for the forfeited purse.

Bathing the dogs also was part of the pre-fight ritual. This prevented owners from gaining an unfair advantage for their dogs by placing poison or drugs on an animal's coat. Otherwise, when an opponent bit the dog, it might be sickened or sedated and lose the fight.

Each fight, according to court records, would "last to the end" — the point at which one dog surrendered or died.

For defeated dogs, though, surviving the fight could lead to an even worse fate.

"At the end of the fight," court documents say, "the losing dog was sometimes put to death by drowning, strangulation, hanging, gun shot, electrocution or some other method."

Other dogs, though, died before they ever got to a formal fight. If animals belonging to Bad Newz Kennels did not test well in training, court records say, "the dogs deemed not to be good fighters would be put to death."

Authorities say seven dogs were killed for that reason and buried on the property in April.

Vick has bred and sold pitbulls and other breeds through two companies: Mike Vick K-9 Kennels and MV7 Inc. (named for his initials and his football jersey number). The companies' Web site — recently taken offline — described their animals as "family pets."

"We do not promote, support or raise dogs for fighting," the Web site said, "and will not knowingly sell, give or trade any dog that may be used for fighting."

-- Staff writer Bill Torpy contributed reporting from Surry County, Va.