The parents of a slain Downey woman are offering a $10,000 reward for clues in a last effort to solve the year-old murder.

Charles and Gloria Morrill are hoping their offer of $10,000 will shake loose a clue, the slightest bit of information that will lead to the arrest of their daughter’s killer.

A year has passed since JoAnne Marie Morrill was slain in her Lindell Avenue apartment in Downey, and police say they have exhausted all leads.

But the Morrills are not ready to give up or to forget. In what they say is a final attempt to put the matter to rest, they ran an advertisement in a local newspaper last month, offering $10,000 for information leading to the arrest and conviction of the person responsible for their daughter’s death.

“It’s just always there,” Gloria Morrill said of the unsolved murder in a telephone interview from her home in Malvern, Pa. “Nothing can bring her back, we know that. What we’re looking for is justice.”

Gloria Morrill is careful to say she thinks police are doing everything they can, and she is sure the “who” and “why” of their daughter’s slaying is a telephone call away.

“My husband and I just don’t believe that there isn’t anybody out there who doesn’t know what went on,” Morrill said. “We thought this might encourage them to come forward.”

JoAnne Morrill left Pennsylvania to join her boyfriend in California in 1980. The couple moved into the apartment building on Lindell Avenue in June, 1984, police said. When things did not work out and her boyfriend moved back to Pennsylvania in December, 1985, JoAnne decided to stay in California

“I think she thought like most people in the East that (California is) the land of milk and honey,” Gloria Morrill said.

JoAnne Morrill was 23, unemployed and living alone when she was killed, said Downey police Detective David Kelly, the investigator assigned to the case.

The last time anyone saw the young woman was Aug. 7, 1986, when she left her apartment and returned home late in the afternoon.

When a friend stopped by the apartment on Aug. 8, JoAnne’s blue 1966 Mustang was parked at the complex. The friend left a note on the door but JoAnne never responded.

After a few days, the worried friend called the police, who found JoAnne Morrill’s body on Aug. 11. They believe she died four days earlier.

The young woman suffered a “violent death” from massive head injuries, and while police have some ideas, they have never established a motive for the killing, Kelly said.

“It appeared somebody had rifled through her property,” Kelly said. A back window was open, the front door was locked and there were no signs of forced entry. The detective declined to release further details of the crime to protect the continuing investigation.

Leads were scarce from the beginning, he said.

“We interviewed everybody in the building and no one came up with anything as far as hearing or seeing anything unusual,” Kelly said. “We got pieces of information . . . but nothing panned out, everything just came to a dead end.”

After a year of dead ends, police suggested that the Morrills offer the $10,000 reward.

“You work anything that you have available to you,” Kelly said. “When they’re (leads) exhausted, you just wait and hope for something to come to light. It’s been just kind of stale here for a considerable amount of time.”

But so far, even the offer of $10,000 has failed to unearth any new clues, Kelly said earlier this week.

“I’m surprised nobody’s called,” he said. “Whoever killed her may have acted alone and kept the information (about the death) very quiet.”

For Charles and Gloria Morrill, $10,000 is not much to pay for justice.

Information concerning the case can be telephoned to Kelly at (213) 904-2332.