Here comes the snow, wind and cold - and when the weather gets to single-digit temperatures, 9NEWS always starts to get questions about pets left in the cold.

When is it OK to intervene? What can law enforcement really do?

We put some of the questions we get most often to Officer Daniel Ettinger of Denver Animal Protection. The interview below has been edited for length and clarity.

9NEWS: It's cold outside, I've seen this dog in my neighborhood, when do I pick up the phone and call you?

Ettinger: The first moment like you feel there's something wrong, it's important to call us. If there's a dog outside and it's very cold, you don't see a doghouse, call us.

9NEWS: When's the threshold though? What do you look for? Do [the animals] have to be outside so many hours? Or the temperature has to be such-and-such degrees?

Ettinger: There's not a specific threshold. We have “extreme temperatures” written into the Denver Revised Municipal Code. We're looking for the dog shivering. We're looking for the dog being unresponsive. Possibly balled up, kind of curled up with its nose tucked into it, trying to recycle its body heat.

9NEWS: It's sort of a judgment call when you get on scene?

Ettinger: It is. We're looking at all the facts. What type of dog is it? If you have a husky outside versus [a small breed dog] that's going to be a different scenario for us. Sometimes these dogs are left outside all of their life, so they're an outside dog and they're more acclimated to being outside.

We see that a lot. There's just a lot of outside dogs in our community and as long as they're provided with the proper shelter, food and water, and they're looked after as well—that's important for people to understand—just because we have a doghouse outside, doesn't necessarily mean that that dog's going to be okay.

It's our responsibility as pet owners to make sure we're watching our pet and knowing what “normal” is in our pet.

9NEWS: We have that hot car law that lets people break open windows if it's an emergency for the pet's life, does that apply to cold weather too?

Ettinger: It does. There's a lot of steps to follow in order to actually break a window and remove a dog. We like to tell people to wait for the experts to get on scene. If it's truly exigent, the dog would be unresponsive. So, what that looks like - if you're banging on the door and maybe you get there and the dog's barking aggressively out the window and then it slowly starts to get into the bottom of the car where the floorboards are, those type of things, you might see it digging. [If] it becomes unresponsive to you being there, that's an element that [tells us] now we need to move a little bit more quickly.

I will say, most times, it's pretty safe for a dog to be in a car for a short period of time in the winter versus in the summertime when it's very dangerous.

9NEWS: You don't see as many problems with cold cars as hot cars?

Ettinger: Not at all.

If you are concerned about an animal in Denver, you can reach Animal Control by calling 311. If you're outside of Denver, look up your county's phone number for that Animal Control office.

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