DEDHAM — Former state chemist Annie Dookhan mixed drugs from unrelated criminal cases to assure positive results and manipulated evidence to increase its weight, a prosecutor said Wednesday, providing the most extensive description yet of the alleged tampering at a Jamaica Plain laboratory.
Assistant Norfolk District Attorney Thomas Finigan said that in some cases handled at the lab, evidence that initially testing negative for the presence of illegal drugs was subjected to retesting and came back positive for contraband. In other cases, the weight of drug evidence was increased, thus potentially elevating the penalties that suspects faced.
The prosecutor outlined the allegations in Norfolk Superior Court as he asked that reputed drug dealer Ismael Perez, who skipped bail two years ago, be released from custody because the evidence against him may be irretrievably tainted.
“We will never be sure if they are the same drugs’’ seized by police in 2008, Finigan told Superior Court Judge Mitchell Kaplan.
The prosecutor did not mention the chemist by name, but officials have identified her as Dookhan, who worked at the crime laboratory operated by the Department of Public Health.
Dookhan resigned in March, and state authorities abruptly shuttered the lab last month after the allegations of tampering emerged.
State Police have notified prosecutors in Eastern Massachusetts that Dookhan handled 60,000 samples from 2003 to 2012, potentially imperiling 34,000 criminal cases.
State Police and Attorney General Martha Coakley, whose office is conducting a criminal investigation, have not disclosed details of the potential contamination of crime samples, beyond an assertion that Dookhan failed to properly document handling of drug evidence one day in June 2011.
In court Wednesday, Finigan provided new insight into the concerns raised by his boss, Norfolk District Attorney Michael Morrissey, and prosecutors from Suffolk, Middlesex, and other counties who routinely sent suspected drugs to be tested and weighed by the lab.
Separately, prosecutors met on Beacon Hill Wednesday with Governor Deval Patrick. Following that meeting, Patrick said he shared prosecutors’ concerns and suggested that a “boiler room’’ be created to review the thousands of cases that might be involved, examine the evidence, and determine the next step.
“The point is to get it to specific individuals, to make sure we are getting to the right cases, and finding out exactly what happened, and that we are dealing with real, live people and real, live cases,’’ Patrick told reporters.
“We prioritize, I hope, those people who may be incarcerated right now because they have a critical liberty interest,” Patrick said. “But we don’t want to limit it to that. But that’s where it would start.’’
Patrick also hinted that some people may lose their jobs over the unfolding scandal. “You are going to hear a lot more about that at the end of the week,’’ the governor said, declining to be more specific.
Cape and Islands District Attorney Michael O’Keefe, vice president of the Massachusetts District Attorneys Association, said the meeting with Patrick and Coakley was productive, with officials adopting a strategy to identify defendants whose cases may have been affected.
“We all have the same goal in mind, which is that the integrity of the criminal justice system be preserved,” O’Keefe said. “We all recognize the district attorneys need additional information in order to make the kind of decisions that have to be made to ensure no one is imprisoned or convicted improperly as a result of the actions that took place at the Department of Public Health laboratory.”
In the meantime, Morrissey’s office is examining cases that it already knows Dookhan was involved with, including that of David A. Danielli, who pleaded guilty to possession with intent to distribute 500 oxycodone pills.
Danielli was originally charged with drug trafficking and faced a mandatory sentence of at least seven years in prison, plus two years for drug sales near a Quincy school. But in February, the state health agency acknowledged that lab protocol had been breached June 14, 2011, the day the suspect’s drugs were tested.
Earlier this year, Morrissey's office dropped its push for the mandatory sentence in return for Danielli pleading guilty and being given a three year House of Correction sentence.
Danielli’s attorney, John T. Martin, filed an emergency motion with the court Wednesday asking that Danielli be allowed to withdraw his guilty plea and be released from prison, a move supported by a prosecutor from Morrissey’s office, George Papachristos.
Papachristos said in court that prosecutors want to keep the criminal case against Danielli alive while the Dookhan investigation continues but do not believe he should remain behind bars when the key piece of evidence against him is potentially tainted.
The requests for dramatic changes in the status of Danielli and Perez were presented to Judge Kaplan, who said from the bench that Wednesday was the first time he confronted the full scope of the Dookhan investigation.
“What are we to do?’’ he asked, rhetorically.
The judge noted that Perez jumped bail and was only back in the Dedham courthouse because he was arrested in Lawrence on drug charges. Danielli, he said, had agreed to plead guilty before another judge, and Kaplan said he did not believe he had the authority to unilaterally reverse that.
Kaplan set Perez’s bail at $1,000 cash — Perez is being held on separate $100,000 cash bail on the Lawrence case — and took the Danielli motion under advisement. Kaplan said he will revisit the matter Friday.
Outside court, Danielli’s attorney, Martin, applauded the prosecutors’ move.
“In our system, many innocent people will stand before a court and say they are not guilty,” he said. “At the same time, many people who are innocent will plead guilty because of the circumstances or evidence they are facing.’’
“When the evidence is false or fabricated, they deserve to be informed of it,” Martin said.John R. Ellement can be reached at firstname.lastname@example.org.