After another weekend of mass shootings, Americans are once again debating the problem of gun violence.
In Texas, Patrick Crusius has been named as the suspect in what has become America’s eighth deadliest mass shooting, after killing 20 people and injuring 26 more in Walmart.
Just hours later, Connor Betts opened fire outside a bar in Ohio, killing nine people including his sister.
He was shot dead by police officers responding to the situation.
Their names now join a roll call of mostly white men attached to the atrocities.
Of 111 mass shootings in the US between 1982 and May 2019, 107 were carried out by men.
The final three are made up of two women, and one case of one man and a woman working together in the San Bernardino attack in December 2015.
According to Statista analysis, in the same time frame 62 of the perpetrators were white, while 19 were black, 10 Latino and eight Asian.
Although there is frequent speculation about the mental health concerns of those who carry out the devastating acts, there is less conversation around whether the gender of the perpetrator is a larger issue.
After Nikolas Cruz was charged with 17 counts of murder for carrying out a shooting at Marjory Stoneman Douglas High School in Parkland, Florida in February 2018, Sky News spoke to experts about the problem.
Professor David Wilson, a criminologist at Birmingham City University, said: “Characteristics of USA school shooters? Male; used legally owned firearms – usually semi-automatic weapons; were ex students of the school they targeted.”
He told Sky News: “What is interesting is that the average gunman tends to be slightly older than we have here [in Florida].
“If you look at the motivation that we know about it does seem to be that men handle their catastrophic loss and self esteem worse than women.
“When the husband or father loses their job or goes through a divorce separation they are thrown out of the home.
“Their status is tied up in their occupation so they seem to suffer more psychologically, which seems to propel them in that way.
“Men also have unequal access to guns and training in using weapons like handguns and rifles.
“Three-quarters of mass murders will use firearms and so that unequal access to the training is relevant.”
Professor Wilson added that men tend to have fewer support networks outside the family unit and their workplace, which can be problematic if one of those breaks down.
He said: “Men all over the world have these experiences, but they don’t carry out mass murders.
“The reason is that we have different gun laws.
“In Florida, we have reports of the gunman’s adoption and his depression, but that is an abstraction.
“It is not the lack of provision of mental health services in the US, but the availability of guns.”
Some of the worst mass shootings in schools in recent years include the Parkland shooting in Marjory Stoneman Douglas High School, the Sandy Hook massacre and the Isla Vista shooting.
Cruz was charged with 17 counts of murder after a shooting at his old school, where he had been expelled for “disciplinary reasons”.
Fourteen more were wounded at the high school in Parkland, Florida, in February 2018.
Elliot Rodger killed six people and injured 14 others before shooting himself dead inside his car on the Isla Vista campus in California in 2014.
Adam Lanza, 20, stole his mother’s guns after shooting and killing her at their home in Newtown, Connecticut on 14 December 2012.
He drove her car to Sandy Hook Elementary School, where he went as a child.
He killed 20 children, six adults and himself within 11 minutes.
Eric Harris and Dylan Klebold attacked Columbine High School in Colorado on 20 April 1999.
They murdered 12 students and one teacher and planted more than 100 explosive devices around the school.
They exchanged fire with police officers at the scene before shooting and killing themselves.
According to the Pew Research Centre, women who own a gun are more likely to have purchased it in later life, and more likely to say protection is the only reason they have it, not just one of the reasons for it.
The centre’s research also indicates that Republican and Republican-leaning women are more likely to support stricter gun laws, particularly around selling to those with mental health issues and the availability of assault weapons, compared with men with the same political leaning.
James Alan Fox, a criminologist at Northeastern University, told CNN: “Women tend to see violence as a last resort, as a self-defence mechanism. You use violence if you have to, if there’s no other way out.
“Men tend to use violence as an offensive weapon, to show them who’s boss.”
He added that men were more likely to own guns, and be more comfortable around them.
Mass shootings have followed a pattern in recent years when carried out by a man, which tends to focus around threats to their masculinity.
There have been suggestions that Cruz was heartbroken after breaking up with a girlfriend, and had got into a fight with her new boyfriend.
Stephen Paddock, who killed himself after opening fire from his hotel room over a concert in Las Vegas in October, did have a girlfriend, but was known as a “loner”.
She said he had grown distant in the final years of their relationship.
Omar Mateen, who carried out the shooting inside an Orlando nightclub, had been described as “mentally unstable” by his ex-wife, who made claims of abuse during their marriage.
The only recent shooting to involve a man and a woman was carried out in San Bernardino in December 2015, when husband and wife Syed Farook and Tashfeen Malik opened fire at an Inland Regional Centre.
Although there were indications both of them had been radicalised to some extent, Farook was also understood to have workplace grievances.
Although some experts disagree on what is classed as a mass shooting, after the 2012 Sandy Hook massacre Congress defined it as a single incident where three or more people are murdered.
This was done to enable states to ask the attorney general to intervene and investigate. In criminology terms, it relates to four homicides or more in a single incident.
Source: SKY NEWS