Anytime there’s a shooting in the news, dread floods Lillian Vasquez.

“Please,” she thinks, “let the victim not be someone with autism.”

Vasquez, whose 25-year-old son is moderately autistic, was dismayed to learn Sunday that a young man with a cognitive disability was shot and killed by an off-duty police officer in a Costco in Corona, half an hour from her home.

The man who was killed, Kenneth French, pushed the officer while waiting in a line for samples, according to his family’s lawyer and the Los Angeles Police Department. An attorney for the officer says he was briefly knocked out by the attack.

“I fear people are going to be afraid of people with autism when things like this happen,” said Vasquez, vice president of the Autism Society Inland Empire.

Although developmentally disabled people are no more likely to act aggressively than the general population, advocates say, dealing with public meltdowns and socially inappropriate behavior is a constant reality for many caregivers. And for the most part, they’re well-versed in how to ease the anxiety that leads to such flare-ups.

But the Costco shooting underscores the need for greater understanding of disability among law enforcement officers and society at large, advocates say.

“If you see someone acting in a way that seems bizarre or doesn’t make sense to you, try to step back and view it from a different lens,” said Donna Norum, chief programs officer of day services for OPARC, a Los Angeles nonprofit that helps disabled people function in the world. “There may be more to this story than you realize.”

What exactly happened at Costco on June 14 is unclear. Surveillance video hasn’t been released, and the incident is still under investigation.

An attorney for the LAPD officer, identified by multiple sources as Salvador Sanchez, said Sanchez was getting a food sample for his son when he was attacked and briefly knocked out by French.

Civil rights attorney Dale K. Galipo, who is representing the French family, said French’s father stepped between him and the officer and explained that his son had a mental disability. Sanchez, authorities say, then shot French, 32, his father and his mother, who were both hospitalized in critical condition.

The officer did not know of French’s disability at the time, sources said.

French’s cousin, Rick Shureih, said French had the mental capacity of a teenager and exhibited behaviors of a “functioning autistic adult.” French was nonverbal and his condition had worsened in recent years, Shureih said, but he wasn’t a violent person.

Advocates say French’s death could have been avoided if the officer had recognized his disability and used deescalation tactics.

People with developmental disabilities like autism sometimes express their needs or frustrations by acting out physically, said Beth Burt, president of the Autism Society of California.

“It could be because of sensory overload. They could be tired, hungry,” said Burt, whose 25-year-old son is on the autism spectrum. “They could end up touching someone who’s wearing something they like or don’t like.”

Those with developmental disabilities “don’t interpret the environment the way we do,” Burt said. Smells, tastes, sights and sounds are felt with greater intensity. She met one adult who ran around frantically when he saw balloons because he was afraid they were going to pop.

Caretakers know how to defuse such situations, Burt said, because they often can identify the cause of — and sometimes prevent — an outburst.

Galipo said a recent change in French’s medication might have affected his behavior.

This did not surprise Vasquez. Her son, Grant, began behaving erratically when his medication dosage was upped recently. He darted around the house, yelled certain phrases repeatedly and displayed uncharacteristic aggression.

A stranger witnessing this conduct may not be aware that someone has a disability. That’s why it’s important for members of the public to not immediately react when someone behaves in what seems like a rude or unusual way, Vasquez said.

“Don’t judge so quickly,” she said. “Maybe there’s more going on. Look beyond your frustration. Offer help.”

If you somehow end up in the crosshairs of a tantrum, said OPARC’s Norum, it’s best to remove yourself from the situation.

“You can’t have a physical altercation if you’re not there to engage with them,” she said.

Caretakers say the Costco shooting renewed fears of law enforcement acting rashly in such circumstances.

And it is far from the first incident to give them pause.

Ethan Saylor, a young man with Down syndrome in Maryland, was dragged out of his movie theater seat by three security guards — all off-duty deputies — in 2013. He died after his larynx was fractured during the altercation.

A transgender teen with autism, Kayden Clarke, who had been frustrated by how his autism diagnosis was making it harder for him to transition, was killed by police in Mesa, Ariz. Officers were responding to a neighbor worried he was about to commit suicide.

Vasquez’s son was kicked to the ground and kneed in the back by an officer when he refused to leave the closed computer area of a public library.

“He wasn’t hurt badly enough for an attorney to listen to me,” said Vasquez, whose husband is a California Highway Patrol officer. “Now people are listening because this young man [French] was killed.”

Fifty percent to 80% of an officer’s encounters are with a person with a disability, according to the National Center on Criminal Justice and Disability. Disabled people are seven times more likely to be the victims of a crime, the center says.

California law enacted in 2015 requires every officer in the state to participate in at least 15 hours of training “relating to law enforcement interaction with persons with mental illness, intellectual disability and substance use disorders.”

Vasquez leads some of these sessions, teaching officers in Riverside and San Bernardino counties how to approach and talk to people with disabilities.

Lower your voice and talk slowly, she tells them. And don’t fire off questions quickly; it may take them awhile to process even the first question.

“If an officer is yelling, that will put the person in fight-or-flight mode,” Vasquez said.

Burt, the Autism Society of California president, has organized a safety presentation in Riverside County in response to the Costco shooting. A task force of government agencies and nonprofits will discuss best practices in deescalation.

Within the first day of registration, 118 people — mostly those with disabilities and their families — signed up.

Burt said parents have called her organization in tears since the shooting, saying they don’t feel safe going out with their children.

“It’s that fear of that could’ve been my child, my adult,” she said.

Margaret Nygren, executive director of the American Assn. on Intellectual and Developmental Disabilities, said it’s important that disabled people continue to feel welcome in public spaces.

“I certainly hope that people won’t be afraid of either off-duty police officers or people with intellectual disability as a result of this particular instance,” she said.