Healdsburg police are investigating the euthanization of a dog at the Healdsburg Animal Shelter after questions were raised online by a dog enthusiast.

Two-year-old Posey, a border collie mix, was put to death four days before Christmas. A rescue group had expressed willingness to take the dog and have a certified trainer work to cure her of dangerous and aggressive behavior toward other dogs.

An article by animal welfare advocate Jen deHaan, who blogs as "dogthusiast," questioned the euthanization despite the shelter's "no kill" policy, prompting city officials Wednesday to ask police to investigate the case.

"My concern when I read the article was it claims a violation of the city ordinance," Mayor Susan Jones said of the city code stipulating "no treatable animal shall be euthanized."

The city contracts with the independently-run shelter for animal services.

DeHaan wrote that Posey was "saveable" and Santa Rosa-based All Aboard Animal Search and Rescue was willing to take her.

"If what she's saying is true, from the city side we need to respond in terms of any violations of ordinances," Jones said, adding "we recognize there are two sides to every story."

Animal Services Manager Judi Adams defended the shelter's decision to kill the dog, saying Posey was dangerous and unpredictable toward other animals.

"There was no indication she would ever be suitable for adoption," Adams said. "We had her here for three months to try to rehabilitate."

During that time, she said, Posey jumped over a fence to attack another dog and, despite work by volunteers and animal behaviorists, showed little improvement and continued with her "lunging, snarling and growling."

"She was showing extreme kennel stress" despite daily walks and exercise, she said.

Adams said a five-member euthanasia committee made the decision to put the dog to death. The committee is comprised of Adams, a veterinarian, a vet tech, an animal behaviorist and a senior staff member.

"It's a very, very hard decision to make. No one likes to take the life of an animal," she said.

The latest controversy comes just more than a year after another flap at the shelter in which prominent chef Douglas Keane sued to prevent the potential euthanasia of Cash, a large Mastiff pitbull mix that also had been surrendered to the shelter by its owner.

Keane, a shelter volunteer, said former Executive Director Julie Seal was obstructing his efforts to adopt the dog.

The lawsuit was dropped after the shelter agreed to release Cash to a dog-training facility.

But the publicity highlighted turmoil and turnover on the shelter's board of directors and problems with a partially completed $3.5 million animal shelter on Westside Road.

The building, across the road from the 1960-built shelter, remains unoccupied. Shelter directors are pursuing a lawsuit alleging construction defects that left the facility uninhabitable.

DeHaan's article last week acknowledged "no kill" does not mean never euthanizing an animal. Instead, it means healthy and treatable animals are not killed or are spared if a qualified rescue partner is equipped and willing to take them, she wrote.

But Adams said a rescue organization needs to demonstrate they are assertively looking for other animals that might be available and needs to request them during the holding period before a scheduled euthanasia.

In the case of Posey, she said, the request from Mary Quinn of All Aboard Animal Search and Rescue came 24 hours before the dog was scheduled to be put down.

Quinn did not return email or phone messages left for her Wednesday.

Adams said the proposal was to put Posey in a boarding-type facility, which she viewed as not easing the animal's stress.

Adams also defended the shelter, which handled 646 animals in 2012 and adopted out 395. Twenty-two animals, including 10 cats, 11 dogs and one rabbit were euthanized because of medical or behavioral problems, she said.

"It's sad when you have a situation like Posey," Adams said. "These situations are unavoidable sometimes."

You can reach Staff Writer Clark Mason at 521-5214 or clark.mason@pressdemocrat.com.