An Edmonton woman who reported a drunk driver last November is angry he was acquitted this week after the arresting officer failed to show up at court to testify.

Lisa Boersma says she first noticed what appeared to be a drunk man stumble out of a south side restaurant.

"He stumbled out to [his truck] — as he's standing there unlocking his door, he's weaving in and out, "she said. "And I just couldn't believe that he got into his vehicle."

Familiar with the Edmonton police "Curb the Danger" program, Boersma says she followed the truck out of the parking lot.

She says the driver was speeding, weaving in and out of lanes and occasionally driving down the centre of the road.

"As we drove down 101st, he decided to hop up on the curb and he actually took the snowbank with air, it almost looked like, and slammed down," she said. "I'm surprised the truck made it through that."

Boersma then called 911 to report the driver — and kept following him for a while longer in order to make sure police stopped the truck and arrested the driver.

"They were on him right away and I was very thankful for that. Score one for the good guys."

But this week, when she went to court to testify about the events of the night, she says the arresting officer never showed up.

And as a result, she says, the case fell apart.

"Turns out if the arresting officer does not arrive, then there's nothing that we can do as a judicial system," she said.

Boersma says she’s upset with how things turned out.

"I was crying," she said. "I've lost a little faith in the justice system."

As CBC’s James Hees found out, the police department is now looking into the case. Alberta Justice says it doesn't track how often police officers don't show up in court.

But Boersma would like to see that change.

"Make sure the police are there," she recommended, "It’s not a small thing. Drunk driving kills [people] all the time."