Social media users were upset by a video that shows a dog tied to a trailer which was attached to the back of an SUV.
Andi Isom said she was driving behind the trailer in Paducah, Kentucky, when her son, who was in the back seat, spotted the dog and started filming.
"I mean, my 9-year-old son could tell this is wrong," she told local station WPSD. "He's always been around animals his whole life, and he loves them."
Isom said she was also upset by the way the dog was being treated.
"Imagine being dangled by your neck and having no control over what's going to happen next," she said.
She called police, but she was unable to give them a license plate number, so they told her there was nothing they could do.
McCracken County Sheriff Jon Hayden said the actions of the person driving the dog were alarming but not illegal.
"I was just asked to look at the video this morning, but certainly folks should be cognizant of the fact that things that you do may alarm or upset others," he said.
Isom posted the video to Facebook, where it has been shared more than 1,000 times and met with outrage and debate about animal safety.
Many who commented were upset by the video.
"How can someone be so stupid? And cruel?" One person wrote.
"What is WRONG with people?!?!" wrote another.
Some, though, said that they did not see any danger to the dog, and speculated that the dog was tied in order to keep it from jumping off the truck into traffic.
"I don't see anything wrong with this. Dogs ride in the back of pickup trucks, on trailers, on top of tool boxes going down the road and none of those have leashes on," reads one comment.
When driving with pets, the Humane Society recommends transporting animals inside vehicles only and placing them inside a crate for added safety.