The actress has filed a lawsuit against Instacart and the shopper.
Actress Angie Harmon is opening up for the first time after her family dog, Oliver, was shot and killed by a driver for an Instacart delivery at her North Carolina home.
"It's so unfathomable to think that there is somebody in your front driveway that just fired a gun," Harmon told ABC News' Juju Chang in an interview that aired Wednesday on "Good Morning America." "And you don't ever forget that sound."
She continued, "I've played law enforcement for 30 years. It's just so different."
Harmon said she put in a grocery delivery order through Instacart in late April to prepare for her family's Easter Sunday celebration.
The former "Rizzoli and Isles" actress said she was communicating with the shopper, whom she thought was a woman named Merle, via text message during the delivery process. She said she later discovered the delivery person's identity, a male, did not appear to match the name or photo on the Instacart app.
"It looked like we were talking to a middle-aged, slightly older woman named Merle who was talking to me and talking to me about my order," Harmon said. "And that's not who showed up at my house."
When the gunshot rang out, Harmon said she was upstairs and heard the reactions of two of her daughters, Emery, 15, Avery, 18, whom she shares with ex-husband, former NFL player Jason Sehorn.
"I think we were in such shock," Harmon said. "I was screaming at Avery to call 911. And when I said that, [the delivery driver] goes, 'No, I'm calling 911. I'll do it.'"
On the call, reviewed by ABC News, the man can be heard telling the 911 operator that the dog was trying to bite him.
"Your dog tried to bite me," the driver says on the 911 call. "I'm sitting here call ya'll. I'm texting y'all. I'm saying can you please put the dogs up."
One of Harmon's daughters also made a call to 911 to report the incident.
Officers from the Charlotte-Mecklenburg Police Department responded to the scene. In a statement to ABC News, a department spokesperson said, "The driver told officers that a dog attacked him while he was at the residence and that he defended himself by firing a single gunshot, striking and mortally wounding the dog."
Harmon told Chang that she did not see any physical indications the delivery driver had been attacked, saying, "No, not at all."
The actress also told Chang a necropsy performed on Oliver showed no signs of having bitten or violently attacked anyone.
Harmon's daughters, Avery and Emery, told Chang they never saw Oliver, a beagle mix, be aggressive toward delivery drivers.
"I order five Amazon packages a day, and it's never been an issue," Avery said.
Describing the personality of Oliver, whom the family adopted from a rescue shelter as a puppy, Avery said, "He's always been very playful, and he was very sweet. When he did pass, it was like a family member was gone."
Following the shooting, the Charlotte-Mecklenburg Police Department closed the case and declined to file charges.
Harmon has since filed a lawsuit against Instacart and the shopper, alleging criminal trespassing and negligence.
"First of all, I think Instacart is beyond responsible for all of this," Harmon said, adding that she and her daughters have struggled with their mental health following the incident. "This didn't have to happen."
Instacart told ABC News it has "permanently deactivated" the delivery driver involved in the incident.
"While we cannot comment on pending litigation, we have no tolerance for violence of any kind, and the shopper account has been permanently deactivated from our platform," the company said in a statement.
Instacart also told ABC News it uses third-party background checks and takes steps to verify drivers' identity. The company said its policy also does not allow the carrying of weapons.
Harmon said she is sharing her story publicly in hopes of raising awareness.
"People need to know that, you know, who they're talking to on Instacart is not necessarily who's going to show up at your house," she said.