Big Island marijuana policing would go up in smoke under a measure on Tuesday's ballot.

Big Island voters will consider ordering authorities to back off marijuana crime enforcement and refuse to spend government money on eradicating the drug. The proposed amendment to county code would make adult personal use of marijuana the lowest priority for police.

"It would save us a lot of money, and it would bring unity between the people and the police," said Adam Lehmann, director of Project Peaceful Sky, which takes its name from the low-flying helicopters used in marijuana raids. "If the people aren't going to tell the police what to do, then who is?"

Police warn that if this measure becomes law, crime rates could increase, and more marijuana would be grown on the island.

"I see homicides related to marijuana possession and use," said Big Island police Capt. Randall Medeiros, commander of the criminal investigations division. "They contend that there's nothing wrong with marijuana. It's not true. ... It affects one's memory and one's ability to converse. It's a quality-of-life and safety issue."

The marijuana question took a circuitous route to get on the ballot.

Project Peaceful Sky gathered nearly 5,000 signatures, but the county found less than half of them to be valid. A total of 4,848 signatures were needed to put the proposal to a vote of the people.

Then the County Council stepped in by voting 5-4 in August to put the measure on the ballot.

If it passes, the Big Island would be the 20th municipality in the country with this kind of marijuana law, Lehmann said. Similar laws are in place in cities and counties of at least eight states.

Under this proposal, the county would not be allowed to accept $500,000 per year it receives from federal and state governments for marijuana eradication, Lehmann said. He estimates that the 1,100 Big Island marijuana arrests in 2007 cost county taxpayers at least $1.1 million.

Community police support groups like the Kona Crime Prevention Committee oppose de-emphasizing marijuana enforcement because it would make police officers' jobs more difficult.

"Police officers can't pick and choose what crimes to protect us from. Indecision kills police officers," said Scott Martin, a board member of the Kona Crime Prevention Committee, a group of citizens that honors policing excellence by treating an officer to lunch every month.

Lehmann argues that police should concentrate on methamphetamine abuse and violent crimes rather than adult marijuana consumption.

"We want safe streets. We love our kids," Lehmann said. "This can be a small message that people here are ready for change."

If the law is approved, legal challenges would likely follow.

The Big Island prosecutor has said he doesn't believe the County Council has the authority to tell its police how to deal with a substance controlled under state and federal laws.