Melissa Fishburn, 41, is legally blind.

Her 4-year-old black Labrador, Knox, helps her get around town and keep safe. As her service animal, he's gone through the rigor and training to be certified as such.

But Fishburn keeps noticing people who like to pretend their pets are service animals - and that makes Knox's job a lot harder.

"It's a problem because if they don't have the proper training, they can be aggressive with him and it can make him not do his job properly,” she said.

It’s why State Sen. Daniel Kagan sponsored a bill that makes knowingly misrepresenting a service animal a crime. It would be punishable by a fine and, in serious cases, jail time.

January will mark one year since the law took effect.

Grocery store chains that supported it, like King Soopers and Safeway, say they aren’t aware of instances when the law has been enforced.

ButKagan hopes it has dissuaded people from faking service animals, which is hard to measure.

“Well I hope it has,” said Kagan. “What I do know is that before we passed this bill, people who were blatantly violating the rules could look at the hotel owner or the supermarket manager and say, 'Huh, whatcha’ gonna’ do about it? It’s not a crime.'”

Emily Harvey, staff attorney at Disability Law Colorado, said since the law passed, the number of calls they get about people with legitimate service animals still having issues with access hasn’t gone down.

"So it's not like this new law has improved access for anyone by keeping fake service animals out of anywhere, so we haven't seen any positive changes come from it,” said Harvey.

"I'm actually disappointed to hear that it hasn't,” Kagan said. “But that's something that might be worth looking into."

There is no registry where people can look up a service animal and Kagan and Harvey would be against creating one. But Melissa likes the idea.

Federal law says only dogs and miniature horses can be trained to be a service animal and businesses are only allowed to ask two questions: Is that a service animal? And what is it trained to do?

Melissa said the state law doesn’t help because people could still lie when asked those questions.

“I still feel like I really don't have anywhere to turn because I really feel like my voice would go unheard if I were to go and say call law enforcement,” said Fishburn. “They wouldn't take it seriously because the law doesn't have enough backing.”