Attorney General Martha Coakley wants disgraced state chemist Annie Dookhan, whose alleged mishandling of drug evidence at a state lab has cast a shadow on thousands of cases, to spend up to seven years in state prison, if she pleads guilty.

In a sentencing memorandum filed in court today, Coakley’s office said that Dookhan deliberately tampered with evidence in criminal cases, ensuring that substances would test positive for drugs.

“With no regard for the consequences, the defendant ensured that samples would test positive for controlled substances thus eviscerating both the integrity of the lab’s internal testing processes, and the concomitant fact finding process that was a jury’s to perform,’’ Coakley’s office said in the nine-page sentencing memorandum filed in Suffolk Superior Court.

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“The gravity of the present case cannot be overstated. The defendant’s actions not only affected the particular individuals named in the indictments but also the entire criminal justice system in Massachusetts,” the memorandum said.

The memorandum was filed in advance of a lobby conference, a meeting between the prosecution, defense, and the judge, that is slated for Friday. The document said that prosecutors were making their recommendation in “contemplation of the defendant accepting responsibility and pleading guilty.”

Neither the attorney general’s office nor defense attorney Nicholas Gordon would comment on the possibility of a plea bargain in the case.

Coakley’s office recommended that Dookhan serve five to seven years in state prison, with five years of probation afterward.

Dookhan faces a total of 27 criminal charges for her actions at the now-closed Hinton State Lab in Jamaica Plain, which was run by the Department of Public Health during Dookhan’s career, from 2003 to 2012, when State Police, who had taken over the lab, discovered her alleged tampering with evidence.

“Given that the motives for the Defendant’s actions were selfish and shallow, coupled with the egregious damage she created for those reasons, significant incarceration is warranted,’’ Coakley’s office wrote. “The sentence imposed by this Court should punish the Defendant accordingly.’’

Hundreds of defendants have been released from custody because of questions raised by Dookhan’s involvement in their cases. The attorney general’s office said that at least 51 who were released have been re-arrested including one man, Donta Hood, who is now charged with murder.

It also said that the state had spent hundreds of millions of dollars, attempting to assess the damage Dookhan inflicted and to mitigate the effect on individuals charged in the affected cases.

The prosecutors acknowledged that sentencing guidelines only called for a sentence of one to three years but urged Superior Court Judge Carol Ball to consider the “extensive collateral repercussions” of Dookhan’s alleged actions.

Boston attorney David Meier, at the request of Governor Deval Patrick, studied Dookhan’s caseload during her Department of Public Health career and concluded earlier this year that her actions may have tainted 40,323 cases.

Defense attorney Gordon asked Judge Ball today to allow him to file his sentencing recommendation under seal, but Ball refused. Gordon provided Ball with a courtesy copy and indicated he planned to file the document on Friday, a court official said.

“The total costs to rectify Dookhan’s actions have climbed into the millions with no end in sight, and the financial aspect does not even address the loss of liberty of affected individuals, the significant deleterious effect on the safety of the public, or the breakdown of public trust in the system,” prosecutors said.

Dookhan faces eight counts of tampering with evidence, one count of perjury, one count of falsely claiming to hold a degree, and 17 counts of obstruction of justice.

Suffolk District Attorney Daniel F. Conley, whose office faces the largest number of Dookhan-related cases in the state, issued a statement, saying, “Annie Dookhan violated her duties as a scientist and a state employee.”

“She betrayed the public’s trust and undermined their confidence in our justice system. What she did will take many years and many millions of dollars to undo, and there is no question that her actions warrant a significant state prison sentence,” he said.