BONNERS FERRY - The Idaho Court of Appeals is affirming a felony drug conviction in Boundary County even though inadequate foundation was laid for testimony on the weight of the marijuana.

John M. Barber was arrested for felony possession of 4.2 ounces of pot during a 2012 traffic stop. The Libby, Mont., man was convicted during a two-day jury trial in 1st District Court and was given a one- to four-year sentence with retained jurisdiction.

Barber appealed his conviction, contending Judge Barbara Buchanan erred by overruling an objection that the arresting officer's testimony on the weight of the marijuana on a digital scale lacked foundation.

Foundation consists of preliminary questions to a witness that are meant to establish the admissibility of evidence.

Barber contended there was no required foundation to show the accuracy of the scale before evidence of weight was admitted into evidence. The officer testified that scale was accurate because the digital scale calibrates itself.

The appeals court ruled that the officer's bare testimony that the digital scale's internal calibration was insufficient to establish its accuracy.

"We hold that a mere conclusory statement that a scale is self-calibrating, standing alone, is not enough to establish accuracy and thereby lay a foundation for the results shown by the scale," Judge Karen Lansing wrote in a Dec. 4 opinion.

However, that deficiency was cured with follow-up testimony that a mechanical triple-beam scale registered precisely the same weight for the marijuana, Lansing wrote.

Chief Judge Sergio Gutierrez and Judge David Gratton concurred.