In the nearly 15 years since a police officer delivered the chilling news that her 4-year-old daughter had plunged to her death from sea cliff, Sarah Key-Marer has waited for the girl's father to take responsibility.

He never did and after two previous juries failed to reach a unanimous decision, a jury Wednesday held Cameron Brown accountable for first-degree murder in the killing of Lauren Sarene Key.

A shocked Key-Marer breathed heavily and began crying as the verdict was read in Los Angeles Superior Court.

"Lauren was our gift from god, the best thing that ever happened to us," Key-Marer said outside court, as she thanked jurors, witnesses, police and prosecutors. "We just learned to live with the pain."

Brown, a former airline baggage handler hurled the girl to her death from a 120-foot cliff in November 2000 because he never wanted the child and was locked in a bitter dispute with her mother over child support and custody, a prosecutor said.

Two previous juries deadlocked over whether Brown was guilty of murder or manslaughter and he has spent nearly a dozen years behind bars awaiting an outcome.

Brown stared straight ahead with no sign of emotion as the verdict was read. After the mother and jurors left the courtroom, Brown told the judge he was innocent.

Brown, 53, faces a mandatory term of life in prison without parole when sentenced June 19 for the murder and special circumstances that he lay in wait and killed the girl for financial gain.

Brown told police the girl tripped and fell as she ran toward the cliff's edge at Inspiration Point in Rancho Palos Verdes.

Defense lawyer Aron Laub argued that his client was a bad dad, but not a murderer and asked jurors to convict him of manslaughter.

"I sincerely believe that is what happened in this case," Laub said after the verdict. "I have great confidence in our jury system, but I cannot agree that this was a just verdict."

The verdict that was nearly 12 years in coming took the jury little more than a day to reach.

Foreman Greg Apodaca said jurors were unanimous from their first discussions and it was a "relatively simple decision to make" after hearing nearly six weeks of evidence and visiting the scenic bluff about 30 miles south of downtown Los Angeles.

"The expert witnesses made it pretty clear and when we did the site visit it was clear to us, as well, that it didn't seem likely that a 4-year-old girl would be up there of her own volition," Apodaca said.

Prosecution experts said the girl's injuries were not consistent with an accidental fall because she couldn't have run fast enough to clear part of the cliff before either striking an outcropping or hitting the beach below.

Jurors heard most of the same evidence as previous juries, but this time Los Angeles sheriff's Detective Jeffrey Leslie bolstered evidence of a financial motive by finding someone who said Brown said it would be "nice to get rid of Lauren" to get out of paying $1,000-a-month child support, Deputy District Attorney Craig Hum said.

"That witness made a significant difference," Hum said, though the primary motive was revenge. "Obviously the financial motive was a factor, but it was primarily his hatred of Sarah, Lauren's mother, that propelled this."

Hum told jurors that Brown's statements were riddled with lies and that Brown had wanted Key-Marer, a British citizen, to get an abortion and he even tried to get her deported.

As a tearful Key-Marer stood to address reporters, juror Shelia Janis said she was sorry for all the pain she had endured.

"I'm sorry for (the) death of your baby, but justice has certainly been served," Janis said. "All the evidence was there."