A 25-year-old man who reached a plea agreement for killing two men will have to serve an additional five years in prison.

Micah Kanahele was sentenced to 20 years to life in prison for the shooting deaths of Greg Morishima, 49, in an 'Aiea garage in October 2003 and Guylan Nuuhiwa, 26, six days later in a Pearl City parking lot.

Kanahele was convicted of manslaughter in the Morishima case and was found guilty of murdering Nuuhiwa after deciding not to contest the charge as part of a plea agreement.

The agreement was conditioned on the Hawai'i Paroling Authority ordering Kanahele to serve 20 years before he could be eligible for parole. But the three-member parole board last month ruled that Kanahele must serve at least 25 years before he could be released.

Even though Kanahele's lawyer Richard Hoke could have withdrawn from the agreement, Hoke did not exercise that option yesterday and the agreement was affirmed.

Hoke said if Kanahele withdrew and went to trial in connection with the Nuuhiwa case, he could have faced a life term even if acquitted of the murder because he was not contesting a related charge of robbing the victim.

Hoke said it would have been "foolish" for his client to expose himself to that stiffer sentence because of the extra five years he now has to serve.

Reach Ken Kobayashi at kkobayashi@honoluluadvertiser.com.