Mass murder or terrorism? Who decides what to call it?

By any definition, the people who ran for their lives in Las Vegas last Sunday felt terror, even terrorized by the man 32 floors above raining down ammunition on them.

Fifty-eight people were killed; mass murder to be sure. But a terror attack? Not according to Las Vegas Sheriff Joseph Lombardo.

"There are motivating factors associated with terrorism, other than a distraught person just intending to cause mass casualty," Lombardo told assembled reporters after the attack.

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In other words, absent any indication the shooter had been motivated by political or religious ideology, the largest mass shooting in modern U.S. history didn't meet the legal litmus test for a terror-related charge.

Taking their cue from police, most news media also declined to call it terrorism, deferring to words like "distraught" and "lone wolf."

That's a problem, says Indira Lakshmanan of the Poynter Institute, a Florida-based journalism think-tank.

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"I think it's important that we as journalists think really hard before we use words. Words have meaning," Lakshmanan says while being interviewed for this weekend's edition of The Investigators with Diana Swain (Saturday at 9:30 p.m. ET and Sunday at 5:30 p.m. ET on CBC News Network).

She points out that, for many people, what happened in Vegas would fit the colloquial definition of terror.

"To feel terrorized is, of course, something that I think one feels from any kind of a violent attack. It doesn't matter what the motivation is. So, in our sort of common parlance, certainly we would all consider that terrorism," she says.

But, Lakshmanan fears that the incendiary labels of "terrorism" and "terrorist" are increasingly being applied in a way that leaves news organizations open to quick judgments that could be wrong.

Only 24 hours before the Vegas shooting, a police officer in Edmonton was thrown into the air after being hit by a car. The driver then allegedly attacked him with a knife before running off and hitting four other people with a second vehicle.

Edmonton police, and indeed Prime Minister Justin Trudeau, quickly referred to it as a terrorist attack, largely because police found what appeared to be an ISIS flag inside the driver's car.

Many news organizations, including CBC News, initially used that as their cue to use the word "terrorism" in their coverage. However, the suspect has still not been charged with terrorism-related offenses.

Noting that the Las Vegas shooter was a white man and the person charged in Edmonton is a Somali refugee, Lakshmanan cautioned that "the media, as well as authorities and politicians, tend to jump to the conclusion that if a Muslim, brown person carries out an attack, it's very quick to appear in the headlines that this was somehow linked to terrorism. Whereas if a white person carries out a similar attack, they're much more likely to call him a 'lone wolf,' 'deranged'but not link it explicitly to terrorism."

CBC News has extensive guidance for its journalists on when to use such words, and are advised to "avoid labelling any specific bombing or assault as a terrorist act, unless the term is attributed."

"Don't judge specific acts as terrorism, or people as terrorists. Instead simply describe the act or individual, and let the viewer, the listener, the reader decide," the guidelines also say.

Lakshmanan says she considers that advice appropriate, but notes that in many small newsrooms around the U.S. in particular, the decisions are sometimes made on the fly.

"It's more sort of, up to the reporter and their editors to determine how they're going to use," such words, she says.

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"I think the larger problem is that, of course, how we write and speak about violent attacks in the news shapes public perceptions.

If we are quick to associate Muslim assailants with terrorism, but not as quick to do the same with white perpetrators, "it certainly creates a perception," of bias, Lakshmanan says.

She suggests it's time those in the news media have a deeper discussion about when, and when not, to use such words.

Also this week on The Investigators with Diana Swain, Las Vegas Sun reporter Ricardo Torres talks the challenges of covering the shooting, and Radio-Canada journalist Cathy Senay on her investigation that revealed dozens of members of the Canadian military also belong to a Facebook page run by a far-right group.