IT STARTED simple: A longtime drug informant accused a narcotics officer of fabricating evidence to frame suspected drug dealers.

But in the 11 months since the Daily News first detailed the allegations lodged by informant Ventura Martinez against Officer Jeffrey Cujdik, the fallout is far from simple, with no conclusion in sight.

An FBI-led investigation, launched in February at the start of the newspaper's "Tainted Justice" series, is moving forward and continually expanding, according to Chief Inspector Anthony DiLacqua, who heads the police department's Internal Affairs Bureau, which is working with the FBI.

"It's quite involved," DiLacqua said. "It's not as simple to close out as other jobs. We're trying to leave no stone unturned. . . . Sometimes we're led somewhere unexpected and we follow another path. There's multiple people with multiple allegations."

In fact, this is the single largest case that Internal Affairs investigators are handling, he said.

The investigation mushroomed in March when the Daily News reported allegations that Cujdik and other members of the Narcotics Field Unit disabled surveillance cameras during raids of bodegas and smoke shops that sold tiny ziplock bags, which police consider drug paraphernalia. After the officers sliced or cut the wires, thousands of dollars in cash and merchandise were missing, the merchants said.

Many of the merchants were hardworking immigrants who spoke little to no English and were not familiar with the criminal justice system. FBI agents have since interviewed many store owners, using translators when necessary.

The investigation took another twist when three women alleged that Officer Thomas Tolstoy fondled, groped or sexually violated them during drug raids.

Cujdik, Tolstoy and three other officers remain on desk duty.

Even though no officer has been charged with a crime, many of their drug cases have been dropped and some drug suspects have gone free.

"[The 'Tainted Justice' series] has forced the Philadelphia District Attorney's Office to recognize that it cannot bring any cases involving these officers as long as this investigative cloud hangs over their actions," said Assistant Public Defender Bradley S. Bridge.

The series has not only impacted pending cases, but more than 50 convicted drug dealers are fighting for new trials, alleging that narcotics officers fabricated evidence against them, Bridge said.

Meanwhile, at least 15 civil suits have been filed in federal court, naming 15 officers and the Police Department as defendants.

One of those lawsuits was brought by Lady Gonzalez, who alleges that Tolstoy fondled her breasts during a drug raid at her Kensington home in December 2007.

Her attorney, Jeremy Ibrahim, is puzzled why the investigation is taking so long, particularly allegations involving Tolstoy.

"I can only surmise that special rules apply when the accused is in the police department," Ibrahim said. "I only hope federal authorities will do what the city authorities are apparently incapable of doing - and that's justice."

Prominent civil-rights attorney David Rudovsky is handling five of the 15 lawsuits; four of the five are bodega owners. Rudovsky said that he plans to zero in on what he views as a lapse in supervision of narcotics officers and their informants, who are paid by the police department for making drug buys.

Police brass have since made major changes in the Narcotics Division. Police Commissioner Charles Ramsey split up the officers in Cujdik's squad and appointed a chief integrity officer to scrutinize drug investigations.

The department also implemented a new 22-page directive on Sept. 11 that places tighter controls on officers and their informants.

"There's a lot more oversight responsibility placed on the sergeants and lieutenants," Deputy Commissioner William Blackburn said.

One major change, said Blackburn, is that a supervisor must witness all payments to informants. "I do think things are working better with the oversight," he said.

As the FBI-led investigation continues, many involved in the criminal justice system anxiously await an outcome.

Guy R. Sciolla, a defense attorney who represents a few suspects arrested by Cujdik, said that it's best for everyone involved, including the officers, for the investigation to wrap up soon.

"You've got police on tenterhooks," Sciolla said. "You've got defendants on tenterhooks. And you've got the District Attorney and defense attorneys in the middle. Problem is, what to do with the open cases? . . . We're all sitting here on standby."