The Hawaii island man who fatally shot his ex-girlfriend seven years ago in front of their 2-year-old son has had his minimum prison sentence cut in half, upsetting family members of the murder victim.

The Hawaii Paroling Authority board set Jeffrey Boyd Santos Jr.’s new minimum at 50 years, compared with 100 set by a previous board in 2008.

"It is very disappointing," said Bev Akimseu, the grandmother of Daysha Aiona-Aka, the murder victim. "Our hearts are heavy. But it’s done. We just have to accept it."

The board set a new minimum because the previous panel didn’t follow proper procedures when it deviated from sentencing guidelines to approve the 100-year term, one of the longest minimums in Hawaii for second-degree murder.

The board’s guidelines call for a minimum of 20 to 50 years for second-degree murder. The agency has the power to exceed the guidelines but must state its reasons for doing so, something the previous board didn’t do.

Santos pleaded guilty to second-degree murder and using a firearm in the commission of a felony for shooting Aiona-Aka in the back of the head in 2006 as their son watched. Aiona-Aka had ended the couple’s stormy six-year relationship and rebuffed Santos’ plea to reconcile.

For the murder charge, Santos received a term of life in prison with the possibility of parole. He received 20 years for the firearm conviction.

Santos must serve one-third of the 50 years before he is eligible to apply for a reduction in his minimum. He becomes eligible in June 2023, according to the paroling authority.

Akimseu said she wasn’t surprised by the authority’s decision but had hoped that board members would have given more weight to the previous panel’s ruling and family testimony opposing any reduction in Santos’ minimum.

At a hearing last month, tearful members of Aiona-Aka’s family had urged board members to keep Santos’ minimum at 100 years, saying that’s what he deserved for the brutal killing and the long-term effects it will have on the family, especially the couple’s son, now 9.

Family members said the son, Dayson Akimseu, cries often because he misses his mother, is unable to share his childhood accomplishments with her and will suffer the rest of his life because of what happened that November day.

Mike Kagami, the Hawaii County deputy prosecutor who handled the Santos case, said he was disappointed but not surprised by the board’s decision. Kagami had asked for a 75-year minimum.

"This board tends to stick to the guidelines," he said.

Santos’ attorney, Brian De Lima, had argued that a 100-year minimum was unfair and akin to a first-degree murder sentence of life in prison without the possibility of parole.

By setting such a high minimum, the paroling board essentially usurped the authority of the Legislature and the courts, De Lima said.

He could not be reached Wednesday for comment.

Bert Matsuoka, chairman of the parole board, said the panel felt 50 years was an appropriate minimum for Santos.

"We’re trying our best to remain within the established guidelines," Matsuoka said.

He stressed that the minimum does not reduce Santos’ overall sentence and does not indicate when he will be released.

Once Santos becomes eligible for parole, the board will consider multiple factors, including feedback from the victim’s family and whether the inmate completed required prison programs, before deciding whether he should be released, according to Matsu­oka.

The Santos case is the latest example of the board revisiting past decisions because a previous board did not follow proper procedures in setting minimum terms.

Matsuoka estimated that the board has revisited about half a dozen to a dozen such cases. In each one, the minimum was reduced to bring it in line with the guidelines, as in the Santos case, he said.

The original minimums in all those cases were set before 2011, Matsuoka said.