HONOLULU -- Prosecutors were forced to give up on Monday in their effort to prevent convicted killer Kirk Lankford from ever being released on parole.

It was a development celebrated by Lankford's family who still say he is innocent.

For Lankford to be denied parole for the death of Masumi Watanabe, a mental health expert would have to find he has a significant history of dangerous behavior and continues to be dangerous. However, even the prosecution's expert could not agree to that. So the effort became futile.

Unable to deny Lankford parole Honolulu Prosecutor Peter Carlisle said he will bring evidence of spouse abuse, a prior sexual assault and even cat killing to the parole board hearing. It is an image disputed by his family.

"We see that the prosecution painted a picture of Kirk being someone really horrible that he's not," Lankford's mother, Trish Sander, said.

She believes her son's account, that Watanabe panicked and died leaping from his truck.

"Kirk is a good person. Kirk has helped people on this island extensively," Sander said.

No longer needed to decide whether Lankford deserves parole, Jurors were finally freed from the case. One said there was quick consensus that Lankford killed Watanabe and lied on the stand.

"I felt that he might have deceived some people, but we have to go with the whole jury, and the whole jury felt that way. So, it was not one individual person that makes decision," juror Phillip DePorto said.

He disputed Lankford's attorney's complaint that they rushed to a verdict.

"We went through everything very thoroughly," DePorto said.

Nearly lost in Monday's legal wrangling was the tragedy of the dead young woman whose body has never been found.

However, Lankford's mother said she has not forgotten.

"I want to make a family apology to the Watanabe family on behalf of the Lankford family, and I want to say we are very sorry for how horribly, horribly Kirk handled all of this," Sander said.

Lankford is still likely to spend most of the rest of his life in prison, but his case still shows that a brand new law offering extra time for dangerous offenders may prove to be difficult for prosecutors to use.