PORTLAND – After a lifetime of academic excellence, a former Bates College professor’s surprising descent was illustrated Monday when she was sentenced to five years in federal prison for her role in a crack cocaine ring.

Linda Williams, 51, was a tenured music professor at the Lewiston college. She pleaded guilty last summer to possessing and conspiring to distribute crack cocaine as part of a ring that intended to sell the drug throughout central Maine.

U.S. District Judge George Singal told Williams she was lucky to be able to hold on to a good job and friends who believed in her while using crack cocaine.

“I have yet to see a defendant receive such an outpouring of support and love and care as has been provided to you,” he said during Williams’ sentencing in federal court. But, he added, Williams’ transgressions let down her supporters.

About 20 of Williams’ friends and family members, including her siblings and professors from Harvard and Indiana universities, attended the hearing. Several gave tearful testimony about Williams’ naive and generous nature, which they said let people she thought were her friends take advantage of her.

“Her generosity took her to the point of not being able to judge the people around her,” her brother, Tecumseh Williams, said.

Linda Williams arrived at Bates in 1996 as a lecturer and was tenured in 2002. She received her doctorate from Indiana University and has a background in African-American music. She had planned to leave Maine to pursue study under a Fulbright scholarship in Cape Town, South Africa, when she was arrested last April.

Williams resigned from the Bates faculty in October.

Prosecutors said Williams let drug dealers stay in her home and use her car to transport drugs. Police raided her home after learning she was about to conduct a $1,000 cocaine deal.

The parade of star professors and successful professionals who testified on Williams’ behalf only emphasized how far she has fallen.

Childhood friend Kathryn Littleton described Williams’ upbringing in Marion, S.C. Williams’ father, an educator and a minister, was a pillar of the community and set high standards for his children, Littleton testified.

“Linda’s always exceeded those expectations,” Littleton said. “Linda was the girl that always did it right.”

Nevertheless, Singal said, she needed to acknowledge the impact the drugs had on people who spent their entire paychecks and sold their belongings to buy crack cocaine.

“Not everyone in Maine is so fortunate to be a crack addict and still live as well as you,” he said.