A 27-year-old former security guard at Howard University was sentenced to three years of probation Thursday for her role in what authorities have called a sophisticated identity theft ring.

Dawn Marshall pleaded guilty in March to a fraud charge in the District’s federal court. So far, Marshall and nine others have pleaded guilty to charges stemming from what prosecutors say was a long-running scheme that netted participants nearly $90,000.

Prosecutors have said the ring victimized more than 175 corporations and people and opened about $1.4 million in lines of credit through scores of fraudulent transactions.

In Marshall’s case, prosecutors said, she swiped information from a Howard University library sign-in sheet and used it to open credit card accounts.

During a hearing Thursday, Assistant U.S. Attorney Sherri L. Schornstein urged U.S. District Judge Henry H. Kennedy Jr. to sentence Marshall to between one year and 18 months in prison — the term recommended by federal guidelines.

“She engaged in conduct with no care for the harm she inflicted on others,” Schornstein said.

Marshall’s attorney, Cary Clennon, said his client deserved leniency because she cooperated with authorities, is holding a steady job and was remorseful.

The attorney noted that she also has a nine-year-old son with special needs. The boy’s father was killed last year during what police have called a domestic dispute with another man at Marshall’s apartment, Clennon wrote in court papers.

In addition to three years of probation, Kennedy also sentenced Marshall to 180 days of home detention and ordered her to pay just over $11,000 in restitution to her victims.