The Thirty Meter Telescope planned near the summit of Mauna Kea on Hawaii's Big Island would be one of the world's largest telescopes.
People are protesting the $1.4 billion project for a range of reasons, including wanting to protect sacred land from desecration, curb development and gain control over local resources.
Prosecuting Attorney Mitch Roth told The Associated Press he will drop the cases against those charged with trespassing, though his office might decide to re-file them later. The remaining people arrested last month were charged with obstruction of government operations.
Roth declined to say why he's moving to dismiss some of the counts but noted they warrant further investigation.
"We don't charge cases unless we can prove them beyond a reasonable doubt," he said.
He added his office will continue to review police reports and video taken at the site.
Kealoha Pisciotta, one of the Big Island leaders behind the effort to stop the telescope, said she's happy to hear some of the cases will be dismissed. "Fundamentally and morally, how can it be trespassing in our house of worship and prayer?" she said.
Kuuipo Freitas said being arrested for trespassing affected her "emotionally, spiritually, culturally."
"Honestly, I wasn't prepared. I didn't intend on getting arrested that day," she said. "It really didn't make sense to be arrested on our own aina (land)."
It's unclear if Freitas is among those whose trespassing charge will be dropped. Her attorney, Dexter Kaiama, who also represents eight others, declined to comment on specifics until a judge has signed off on the dismissals.
Kaiama said he has no reason to believe a judge won't approve the motions for dismissal that have been filed. The next court date in the case is scheduled for June 18.
Construction on the project has been halted since last month amid protests and arrests of opponents blocking crews from accessing the site.
Gov. David Ige previously said it's up to the non-profit company behind the telescope to determine when work will start again. "And we will support and enforce their right to do so," he has said.
A company spokeswoman said officials don't know yet when construction will resume. She declined to comment on the charges being dismissed.
Pisciotta said protesters will remain on the mountain, despite the possibility of more arrests.
Freitas plans to be among them. "We're not letting them through," she said of the construction workers.
Earlier this week, Ige said the project has the right to move forward. But he promised major changes in stewardship of Mauna Kea, listing 10 actions he would like to see from the University of Hawaii, which leases the land. They include beginning to decommission some of the 13 telescopes already on the mountain.
The governor also urged the university to significantly limit non-cultural access to Mauna Kea, and to legally commit that this is the last area of the mountain where a telescope will be considered.
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