In 1997, Michael Procopio - then a 22-year-old shipping clerk - invited a deaf woman who had been a childhood friend to his parents' house in South Philadelphia, led her to the basement, and raped her.

This week, federal prosecutors hope to persuade a jury to set that past aside and consider Procopio and 17 others, most with criminal histories of their own, as victims in what Police Commissioner Charles H. Ramsey has described as "one of the worst cases of police corruption I have ever seen."

Opening statements are scheduled to begin Monday in U.S. District Court in the trial of six narcotics officers accused of running the streets with ganglike tactics for years.

To hear prosecutors tell it, the group - all assigned to the Police Department's South Narcotics Field Unit - routinely trampled over the rights of drug suspects, stealing more than $500,000 in cash and drugs while using excessive force and falsifying police reports to downplay their take.

The trouble is, it won't be prosecutors telling that story after Monday's opening statements.

The government's case hinges on getting a jury composed largely of suburban residents to believe the word of convicted dealers, drug users, and forgers over that of veteran officers, many of whom have racked up commendations in their lengthy careers.

And that, say lawyers for Officers Thomas Liciardello, Brian Reynolds, Michael Spicer, Perry Betts, Linwood Norman, and John Speiser, is their clients' greatest advantage.

"It's their word against our word," said Reynolds' lawyer, Jack McMahon. "Almost to a man, these guys are admitted drug dealers that were out there doing the things that our clients were charged with stopping."

Procopio's past became a flash point in that regard last week, with lawyers on both sides engaged in a last-minute, behind-the-scenes argument over whether the jury should be told about his rape conviction.

He pleaded guilty to one count of sexual assault in 1999. His accuser, a 22-year-old woman who had known Procopio, who is also deaf, since their childhood in Mayfair, described the brutal attack in an early court hearing in his case.

She said Procopio led her to his parents' basement, pulled down her pants, and forced himself upon her.

"I told him to get off me," the woman testified. "I was trying to get up. I felt threatened. He started to shush me."

Procopio, now 40, served his sentence and has not been charged with a violent crime since, said his lawyer, Michael Pileggi, who represents him in the civil suit against the indicted officers.

"That happened nearly 20 years ago," Pileggi said. "The argument is whether the prejudice that information would put in the minds of a jury outweighs its value as evidence of his credibility."

Since his conviction, Procopio has had problems with prescription pills, including a 2009 conviction for drug dealing and an arrest for possession in 2012.

Liciardello is listed as the arresting officer in that first drug case, Speiser in the second. City prosecutors, who stopped accepting cases from them and their five codefendants in 2012, withdrew Procopio's latest charges soon after his arrest. His lawyer has filed to have his 2009 conviction overturned.

But whatever Procopio's past sins, Pileggi said, they don't excuse what the officers of the field unit are alleged to have done to him.

According to court filings, Procopio twice ran afoul of the group - first in December 2008, when Liciardello and Reynolds allegedly seized $18,000 and a Rolex watch during a search of his home. Liciardello reported only $4,750 as seized and made no mention of the alleged watch in his police report.

What's more, investigators say, he used Procopio's money to order pizza for other officers while they conducted the search.

Four years later, Procopio says, Liciardello, Reynolds, and Speiser targeted him again, pulling his car over and seizing $3,900. Prosecutors said Speiser failed to state in the incident report that they seized any money.

The 42-page indictment against the officers is filled with similar allegations of misconduct:

Drug suspect Michael Cascioli says he was dragged inside his City Avenue apartment in November 2007 and beaten by the group until he directed them to another man's money and drugs. Later, two of the officers purportedly dangled Cascioli over an 18th-floor balcony until he gave up the password to his PalmPilot.

Another man is expected to testify that the officers stole $12,000 and held him in a dank hotel room for days while threatening his family if he failed to cooperate with them.

Already, dozens of federal civil rights lawsuits have been filed against the officers, and local courts have tossed about 450 of their former drug cases.

"This case is in many ways outrageous, with people being hung out over balconies, people having their teeth knocked in, people being hit on the back of the head with steel bars," Assistant U.S. Attorney Anthony Wzorek said at a hearing last year.

Still, it is not as though Wzorek is unaware of the challenge posed by his witnesses' lengthy rap sheets. He, co-counsel Maureen McCartney, and the FBI have spent years working to corroborate their stories and shore up their case with outside evidence.

In the last two weeks, they have withdrawn multiple charges tied two witnesses, whose recent actions only underlined their credibility issues.

One was arrested in a multicounty drug investigation last month. The other, it was discovered, had told three different versions of his encounter with the narcotics squad during his criminal trial, his testimony before a federal grand jury, and in a civil lawsuit he filed against the indicted officers.

Prosecutors have amassed hundreds of thousands of pages of police reports and other documents and prepped outside witnesses ranging from Internal Affairs investigators to the lawyers who represented their witnesses in criminal trials.

They also intend to show video of an attempted sting they set up hoping to catch a rogue narcotics squad in action.

According to court filings, in April 2012 the FBI tried to catch Liciardello and the others in the act by feeding information through a cooperating informant that a contact would be making a cash pickup after a drug deal.

After monitoring the car the informant had flagged, which was driven by an undercover agent, Liciardello and other officers pulled it over in Delaware County. They found nearly $8,600 in the back of the car. They reported all of it.

Wzorek has said the video shows them conducting an illegal search of the car outside their jurisdiction.

Defense lawyers see something else entirely - an FBI sting that went awry.

"The FBI wanted them to steal the money," Liciardello's lawyer, Jeffrey Miller, said in an interview this month. "They found $8,600. They reported $8,600. The sting completely blew up in the face of the government."

But it could be the government's star witness - one of the narcotics squad's own - who does the most to either corroborate the narrative presented by prosecutors or sink the case on witness credibility issues.

Wzorek has said Jeffrey Walker, a 24-year veteran of the force who pleaded guilty to robbing a drug dealer last year, proved key to building the indictment against his fellow officers.

Soon after he began cooperating with investigators, he flagged dozens of the group's cases in which illegal activity occurred. He said he personally participated in shakedowns of some of the drug suspects set to testify in the government's case.

To the defense, however, Walker is just another criminal lining up to tarnish their clients' good names.

As Reynolds' lawyer McMahon put it in an early court motion: "The government now takes . . . unfounded and unsubstantiated cases and with a wave of the wand from a drowning, despicable rat, turns garbage into gold."

The trial is expected to last 10 weeks.

215-854-2608 @jeremyrroebuck