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Virginia Court Upholds DNA Fingerprinting Evidence in Murder Trial

September 23, 1989

RICHMOND (AP) _ The nation’s first murder conviction based on the use of so-called DNA fingerprinting evidence was upheld Friday by the state Supreme Court.

In a pair of unanimous rulings, the court concluded that DNA tests which linked Timothy Wilson Spencer to the rape-slayings of two women were scientifically reliable.

DNA, deoxyribonucleic acid, is the basic genetic material in human cells. Scientists believe that everyone, except for identical twins, has a unique DNA pattern.

Spencer, 26, a former resident of a Richmond halfway house, was convicted of murder and sentenced to death in separate trials last year for the slayings of Susan M. Tucker, 44, of Arlington and Debbie Dudley Davis, 35, of Richmond.

The women were bound and strangled by an assailant who broke into their homes through a window. At both trials, evidence was offered that semen samples from the crime scenes and blood samples from Spencer had matching DNA patterns.

In DNA analysis, microscopic fragments of thread-like genetic material are treated so that they arrange themselves into characteristic patterns which look much like the bar codes used by supermarket scanners.

If pattern samples from crime scene match the suspect’s, the blood or semen is considered to have come from the suspect, since the likelihood of matching patterns from different people is reckoned at 1 in many millions.

The state Supreme Court said Spencer’s challenge to the DNA evidence amounted to saying ″that we should hold off until another day″ any decision on the reliability of such tests.

But a number of expert witnesses testified that the technique is generally accepted in the scientific community.

″Indeed, Spencer acknowledges that the evidence establishes that the DNA tests are accepted ‘as reliable within the scientific community’ and that he ’was unable to find or produce one qualified expert to debunk either the theory of DNA printing or the statistics generated therefrom,‴ the court said.

Earlier this year, Spencer was convicted and sentenced to death in two other cases, the rapes and murders of Dr. Susan Elizabeth Hellams, 32, of Richmond, and Diane Cho, 15, of Chesterfield County.

Both those cases are still on appeal.