The mother of murder victim has said she does not believe her killer will ever reveal where her body is.
Nat Fraser is serving a life sentence with a minimum term of 17 years after being convicted at a retrial in 2012 of organising the murder of his wife.
The mother-of-two disappeared from her home in , Moray, in April 1998.
Her body has never been found.
The trial heard a claim that told a former friend that he paid a hitman £15,000 to kill his wife after she began divorce proceedings.
Now, her mother has said Fraser's refusal to admit his guilt means she believes he will never confess where his wife's remains are.
But she said plans to bring in "Suzanne's Law" - allowing the parole board to factor in if killers refuse to reveal the location of their victim's body when ruling on release - would be a "step in the right direction" for families in their situation.
In an interview, she said: "[Fraser] would need to admit to his family that he was guilty.
"They've never attended any of the trials that he had, so they don't hear the evidence, so naturally they're going to think that he's innocent.
"So, if he was to admit to where 's body is, that's admitting to his family as well that all these years they've thought the wrong thing.
"That's basically the reason, I think, that he'll never let us know where she is."
Arlene's sister, Carol Gillies, said the family was "left with the feeling that is still out there", adding: "Where is she? Will we ever find out? One day you might think 'I'm never going to find out', the next day you think, 'well, maybe I will'."
She continued: "At the moment I feel the law is helping [ ] because he'll have served his sentence for murder and he would get out.
"This is where I think we need help from the government.
"If he was up for parole next week and they said, 'oh, you know, you've been a model prisoner, you're released, have a nice or life or whatever', where does that leave us?
"We're no further forward. We continue to live the sentence whereas he doesn't.
"I also feel if you're withholding information, something really important, a body, surely when he's released from prison he's continuing to commit a crime against us?
"He's continuing to lie to his family, lie to the police, and this is where I think there needs to be a change in the law."
The Scottish Government plans to amend existing parole board rules to allow a prisoner's failure to disclose the location of a victim's body to be taken into account when deciding if parole should be granted.
The family of Edinburgh murder victim Suzanne Pilley - killed by her former lover in 2010 - have pressed for the change as he has never revealed where her body is.
Thompson said she believes the change would be "a very good thing" but does not think it would help in her daughter's case due to Fraser's refusal to admit guilt.
