El Paso, Texas ? The expert witness whose testimony helped convict a man of a rape he didn’t commit was a novice who had been warned by a supervisor that he needed to learn more about the basics of blood analysis, a newspaper reported.

Glen David Adams, a chemist at the Department of Public Safety laboratory in Lubbock, got a D in his serology course at Texas Tech University and faced a “significant backlog” of cases as he worked on the rape investigation, according to documents obtained by the El Paso Times under the Texas Public Information Act.

Serology is a science dealing with bodily fluids such as blood, semen, saliva, sweat or fecal matter.

Brandon Lee Moon, who is now 43 and living in the Kansas City area, was convicted in the 1987 gunpoint rape of an El Paso woman and was sentenced to 75 years in prison. Adams was a key witness in the trial, testifying that Moon was among 15 percent of the population who could be responsible for semen stains found on the victim’s bathrobe and comforter.

But Moon was exonerated last month when DNA tests proved he couldn’t have been the source of the semen stains. Scientists who conducted those tests said Adams’ work was badly flawed.

Adams did not return phone calls placed by the newspaper.

The state Senate’s Criminal Justice Committee plans to investigate all of Adams’ DPS work, said Sen. John Whitmire, D-Houston, the committee’s chairman.

Adams began working as a chemist for the DPS in November 1986. A June 1987 evaluation rated him “some improvement needed” in job knowledge and planning and organization.

Despite the negative review, Adams was assigned to the Lubbock lab two months later. One of the first cases he handled was Moon’s.

Adams’ report on the case said the semen stains came from a “non-secretor,” or a person who does not secrete the antigens for his or her blood type into other bodily fluids.

Adams said Moon was a non-secretor, meaning he could be responsible for the stains. He said the victim’s husband and son were secretors, meaning they couldn’t be responsible for them.

But DNA tests analyzed last fall showed the semen stains on the comforter came from the victim’s husband. And the tests showed the robe stain did not come from either Moon or the husband.

Moon said Adams’ employment records raise serious questions about the quality of his work.

“If there are questions in my case, there are questions in other cases,” he said.