BY DAWN HOBBS

Who killed Lori Rosen?

For the past 25 years, it's likely no one has known except her killer.

But the mystery may soon be solved.

The 19-year-old Santa Barbara City College student was found strangled to death in her Montecito apartment in March 1977.

Sheriff's detectives gathered numerous pieces of evidence from the scene, some of which could contain DNA — but technology wasn't advanced enough then to possibly determine who murdered the girl.

Detectives recently submitted the evidence to the state Department of Justice forensic laboratory in Goleta hoping technological advances could help track down the killer.

Unsolved homicides are also under review at the Santa Barbara Police Department, where a special Cold Case Unit was recently established. Detectives there are wading through tons of material in an effort to determine which unsolved cases have DNA evidence that may be helpful in identifying the killers.

Criminalists at the lab determined that evidence from the Lori Rosen case is intact enough to test. Once analyzed, the DNA typing will be entered into the state's Cold Hit databank. If Lori's killer has been convicted of a felony in recent years, his DNA sample may be in the databank — and, now, 25 years later, he could finally be brought to justice. If the killer's DNA is not in the databank, detectives plan to obtain samples from original suspects.

Traditionally, DNA analysis was primarily used in cases where a suspect had been identified. Until recently, law enforcement agencies hadn't used DNA analysis to identify a suspect.

However, in the past three years authorities in California and several other states have made a concerted effort to create databanks with the DNA of convicted felons. Now, law enforcement officials can use DNA technology not only to establish guilt of a known suspect — but also to find the killer among a large pool of criminals.

"These are cases that would not have been solved," said Charlene Marie, senior criminalist at the state lab.

As more laboratories across the state upload DNA samples in the databank, chances increase that a suspect will be identified.

"Sooner or later I expect we will get hits on these cases," said Ms. Marie. "I think this will be extremely far reaching, really change things and get some bad people off the street."

Convicted killers have always been required to provide DNA samples for an FBI database, but it's been optional for other felons. However, legislation passed this year allows state prison and local jail officials to take samples from convicted felons without a court order and by force. Earlier this month officials finished gathering DNA samples from more than 600 Death Row inmates to see if they can be linked to unsolved murders.

Ms. Marie pointed to a recent case to illustrate the growing effectiveness of the Cold Hit databank.

"There was a 13-year-old girl who in 1984 was sexually assaulted and murdered," she said. "Her case was never dropped, but there were never any hits either. He was in prison for failing to register as a sex offender in another conviction and was due to be let out in two weeks when there was a hit. It's very powerful."

There were 30 hits statewide last year. But with more samples being entered into the databank, there were 30 hits last month alone.

"As the databank increases and the number of samples increase, the number of hits will drastically increase," Ms. Marie said.

The databank currently has about 205,000 offenders listed by DNA. So far, 854 cases have been uploaded to compare and, of those, 72 matched. The criminalists at the Goleta lab met a Dec. 2 deadline to submit screened DNA samples to the Sacramento lab for analysis from about 70 local cold cases that had salvagable evidence.

Now, it's a matter of waiting to see if there are any hits.

The Cold Hit Program was launched in October 2000 with a $50 million grant from the Governor's Office of Criminal Justice Planning.

The Bureau of Forensic Services has been working with law enforcement agencies to process backlogged evidence through public and private laboratories. Both Sheriff's department and Santa Barbara Police detectives have recently spent many hours poring through cold cases to determine if there's evidence they can submit.

The resulting DNA profiles will be cross-referenced against the databank of known offenders. The database is also part of a national DNA system known as CODIS, or the FBI Laboratory's Combined DNA Index System. The DNA profiles originate locally and then go to the state and national levels. CODIS blends forensic science and computer technology into an effective tool for solving violent crimes, enabling local, state and federal crime labs to exchange and compare DNA profiles electronically.