More than likely through "extra-occupational action".
UPDATE from the Boston Herald
Dookhan, 34, pleaded not guilty this afternoon in Boston Municipal Court to two counts of obstruction of justice and falsely pretending to hold a degree from a college or university. She is expected to post $10,000 bail, her attorney said.
Prosecutors said today Dookhan would sprinkle cocaine on negative test results, test them again, and report the positive finding; and test one sample out of a batch of 25 and list them all as positive.
Coakley added Dookhan could face more charges as the investigation continues. Each obstruction charge carries a sentence of up to 10 years in prison.
“This is not the end of the charging,” Coakley vowed.
State police arrested Dookhan this morning at her home in Franklin, leading her out of her modest split-level after handcuffing her inside shortly before noon. She did not speak and kept her head down as she was led down her walkway in front of reporters to one unmarked police car, then again to a cruiser which sped away up the suburban street not far from Interstate 495 with the rogue chemist inside.
Dookhan wore jeans and a hooded sweatshirt. A man at Dookhan’s home told the press after, “Please, get off my property.”
Dookhan must wear a GPS monitor while out on bail and surrender her passport, a judge ordered. She must also stay away from a former employee.
Coakley said she was determined to find Dookhan’s motive to prevent future lab breaches and acknowledged Dookhan’s ego and the need to feel proud that she was an efficient worker may have played a role in her actions.