Tom Jackman has been covering criminal justice for The Post since 1998, and now anchors the new "True Crime" blog.)

Former Massachusetts crime lab chemist Annie Dookhan at a hearing in November 2013 where she pleaded guilty to obstruction of justice, perjury and tampering with evidence. She was sentenced to three to five years in prison, and was paroled in April 2016. Before Massachusetts discovered in 2013 that one of the chemists in its state crime lab was actually using the drugs she was testing, it uncovered another chemist in 2012 who admitted she had been falsifying some of her drug testing results for more than nine years. Both chemists were arrested, pleaded guilty and served prison time. So what should happen to the tens of thousands of cases processed by Sonja Farak, in the Amherst lab, and Annie Dookhan in the Boston lab? In Dookhan’s case from 2012, county  The Washington Post;prosecutors determined in May of this year that her test results were involved in more than 24,000 convictions. The number of Farak cases has not yet been determined but is likely to be high as well. Now the American Civil Liberties Union and the Massachusetts public defender are asking that, in light of the failed “War on Drugs” and the damage these cases have already done to mostly low-level drug users, all 24,000 of the Dookhan-related convictions should be thrown out. No way, say the prosecutors in the eight counties around Boston where Dookhan handled drug evidence. They want each case individually reviewed, in the interests of justice and the fact that Dookhan was rarely the sole source of evidence against a drug defendant. They say they have already processed about 1,500 cases from defendants who came forward after news of Dookhan’s misconduct first emerged, and there’s no need for a blanket amnesty now. It’s another blow to the crime lab business, already reeling from federal criticism of their long-trusted sciences like bullet and tread analysis, reports of sloppy work at the FBI crime lab, and now massive misconduct by a top state chemist. And then another. In the same state.........So even though the Supreme Judicial Court, Massachusetts’ highest court, ruled in 2015 that a blanket dismissal of all cases was not appropriate “at this time,” the ACLU this week returned to the high court to renew their call for a “global remedy.” The defense wants all 24,000 convictions either dismissed permanently, or dismissed with the option for prosecutors to retry cases where there exists sufficient untainted evidence for another conviction. Carrie Kimball-Monahan, a spokeswoman for the Essex County district attorney, said in every case retried so far in Essex, the drug evidence was confirmed as Dookhan had tested it originally.........“The notice that the District Attorneys have started sending out is truly awful,” Keehn of the public defender wrote in a motion seeking to have the letter stopped. He said it effectively pledged to recipients there would be public defenders available to represent them, and there were not enough lawyers. “The burdens of a systemic lapse are not to be borne by the defendants who are its victims,” he wrote. Wark said the defense bar’s refusal to cooperate after May cost them the chance to review the translation, and “it was translated by a native Spanish speaker who didn’t learn English until she was 16.” The high court declined to stop the prosecutors from sending the notice, but instructed them to keep copies of the letters and any responses they received. Segal said the letter irreparably damaged the process of case-by-case appeals. Wark and Kimball-Monahan said prosecutors stand ready to handle any appeals which come in. The Massachusetts Supreme Judicial Court will hear arguments from both sides in November."