--- description: Prosecutors in Massachusetts dropped more than 23,000 cases on Tuesday, dismissing convictions that were tainted by a rogue lab technician title: Massachusetts Prosecutors Drop 23,000 Drug Convictions Tainted by Lab Chemist image: https://static.time.com/v3/assets/bltea6093859af6183b/bltc1b2b4d41f8c5d40/6988c37b2dce01046a9ed1ad/massachusetts-state-lab-convictions-overturned.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  * [U.S.](/section/us/) ## U.S. Update your preferences in [Account Settings](/account/preferences/) Close # Massachusetts Prosecutors Drop More Than 23,000 Drug Convictions Tainted by Lab Chemist  by [Katie Reilly](/author/katie-reilly/)  ## Katie Reilly Update your preferences in [Account Settings](/account/preferences/) Close Apr 19, 2017 1:03 AM CUT  Hinton State Laboratory Institute Hinton State Laboratory InstituteTamir Kalifa—The Boston Globe/Getty Images  by [Katie Reilly](/author/katie-reilly/)  ## Katie Reilly Update your preferences in [Account Settings](/account/preferences/) Close Apr 19, 2017 1:03 AM CUT Prosecutors in Massachusetts dropped more than 23,000 cases on Tuesday, dismissing convictions that were tainted by a lab technician who tampered with evidence and fabricated results. More than 23,000 low-level drug cases were dropped, while prosecutors decided to re-prosecute a few hundred of them, [NBC News reported](http://www.nbcnews.com/news/us-news/epic-drug-lab-scandal-results-more-20-000-convictions-dropped-n747891 "undefined"). The lab technician, Annie Dookhan, worked at the William A. Hinton State Laboratory Institute in Boston from 2003 to 2012, during which time she was responsible for testing drugs in about 40,000 cases, the [Boston _Globe_ reported](https://www.bostonglobe.com/metro/2017/03/25/most-drug-cases-handled-former-state-chemist-annie-dookhan-have-been-vacated-case-nears-end/yfa6MU9P8HLdA3irE4tgnM/story.html "undefined"). She served three years in prison for perjury and evidence-tampering and was released last year on parole, according to the _Globe._ Defense advocates had called for a full dismissal of any case Dookhan worked on, while prosecutors had argued that defendants should be responsible for challenging their convictions. Instead, the Massachusetts Supreme Court ruled that prosecutors should keep a small percentage of the affected cases and drop the rest, NBC News reported. Tuesday marked the deadline given to prosecutors for determining which convictions to dismiss or preserve. ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4745717/massachusetts-prosecutors-convictions-dropped-annie-dookhan/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4745717/massachusetts-prosecutors-convictions-dropped-annie-dookhan/"},"headline":"Massachusetts Prosecutors Drop More Than 23,000 Drug Convictions Tainted by Lab Chemist","datePublished":"2017-04-19T01:03:04.000Z","dateModified":"2026-02-23T04:29:05.680Z","description":"The chemist admitted to tampering with evidence","url":"https://time.com/4745717/massachusetts-prosecutors-convictions-dropped-annie-dookhan/","keywords":["Crime","Massachusetts","onetime"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/bltc1b2b4d41f8c5d40/6988c37b2dce01046a9ed1ad/massachusetts-state-lab-convictions-overturned.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Katie Reilly","jobTitle":null,"url":"https://time.com/author/katie-reilly/"}],"articleSection":"U.S.","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/bltc1b2b4d41f8c5d40/6988c37b2dce01046a9ed1ad/massachusetts-state-lab-convictions-overturned.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Hinton State Laboratory Institute","caption":"Hinton State Laboratory Institute","creditText":"Tamir Kalifa—The Boston Globe/Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/us/","name":"U.S."}},{"@type":"ListItem","position":2,"item":{"@id":"https://time.com/4745717/massachusetts-prosecutors-convictions-dropped-annie-dookhan/","name":"Massachusetts Prosecutors Drop More Than 23,000 Drug Convictions Tainted by Lab Chemist"}}]}] ```