Opening fire with an AK-47 assault rife in the parking lot and inside a busy Walmart in El Paso, Texas at 10: 00 AM local time, 21-year-old Patrick Crusius, killed 20, injuring 30 more, with several victims ranging from 2 to 82 in critical care. Crusius was taken into custody by El Paso police without incident, giving law enforcement—and behavior scientists—an opportunity to determine motive, something not obvious in mass shootings. El Paso Police Department Sgt. Robert Gomez described the carnage where Crusius opened fire in a densely populated soft target where the most carnage takes place. Today’s ballistic episode was in the top 10 of deadliest shootings in U.S. history, reminding Texas, and other pro-Second Amendment states, that there’s little law enforcement can do to prevent violent episodes before they occur, often not knowing the killer’s motives.

Internet searches turned up a racist manifesto attributed to Crusius, hinting at a possible motive related to a hate crime. But whatever law enforcement finds, the fact is that another youthful offender went over the deep end, gaining access to deadly firearms, then finding a sick excuse to commit mass murder. Like the deadly Oct. 1, 2017 shooting from atop the Las Vegas, Mandalay Bay Hotel by 55-year-old Stephen Paddock, killing 58 [including Paddock], injuring 85 innocent concert-goers, police could not find a motive, as if it really matters. When it comes to mass killers, whether young or old, the objective is to kill as many people as possible, regardless of what motivates the violence. Crusius and Paddock both picked soft targets, where densely concentrated people made the mass killing like shooting fish-in-a-barrel. Terrorists, whether Mideast or otherwise, pick the same kind of soft targets.

Police estimated that Walmart had at least 1,000 employees and about 3,000 shoppers busy buying back-to-school gear for their children. El Paso’s Del Sol Medical Center treated at least 11 victims at their trauma center, with local authorities putting out an urgent call for blood. Another 13 victims were treated at University of El Paso Medical Center, with at least two children aged 2 and 9, treated for gunshot wounds. Vitalent Blood Services requested urgent blood donations to accommodate the victims. Eyewitness shopper Vanessa Saenz saw Crusius, clad in cargo pants, black tee shirt and wearing ear-buds, open fire taking down a women, “dancing around.” “One thing I’ll never forget is when he walked into Walmart very confidently like he was on a mission,” Saenz told ABC News. To kill 20, injuring 30, in short order showed the extent of Crusius preparation for mass murder

Located at the popular Cielo Vista Mall in El Paso, Crusius staked out his scene carefully, knowing the density of shoppers on a busy Saturday. Cielo Vista was popular with Mexican day-shoppers, traveling across the border to shop at Walmart. If reports about Crusius’s manifesto are true, he weighted into the border crisis, one on the most divisive issues of the 2020 presidential campaign. If Crusiius acted from rage-against-illegal aliens, his act would qualify as a hate crime. “We’re in shock over the tragic events at Cielo Mall in El Paso,” Walmart said in a statement. “We’re praying for the victims, the community & our associates, as we as the first responders. We’re working closely with law enforcement & will update as appropriate,” making no comments about the motive or what to do to prevent it. New York Gov. Andrew Cuomo signed the nation’s most restrictive gun-buying legislation this week.

Most Second Amendment advocates don’t want more government restrictions on gun purchases. But something must be done to stop mentally ill individuals from buying firearms. New York’s new law lengthens the time for gun purchases from 3 to 30 days, giving authorities more time for background checks. Whether increasing the waiting period for gun buys makes a difference or not is anyone’s guess. Federal Authorities, with the Bureau of Alcohol, Tobacco and Firearms [ATF], don’t have a mental health data base available to check the mental health histories of guy buyers. Increasing the buying period to 30 days can’t hurt but federal authorities need a mental health database, something that currently violates federal medical privacy laws. If federal authorities are serious about preventing mass murder, they need a readily available mental health database.

Listening to elected officials express their “sadness” over mass murder does nothing to prevent it in the future. Since banning firearms isn’t in the cards, it’s only right for ATF to take extra measures to ascertain the mental health fitness of gun buyers. Congress must change current medical privacy laws to exempt individuals when they decide to buy lethal firearms. Only by developing an accessible mental health database can authorities intercept potentially mass killers before they buy firearms. “I just ask for everyone’s strength for El Paso right now, everyone’s resolve to make sure that this does not continue to happen in this country,” said 46-year-old former Congressman Beto O’Rourke (D-Texas), now a 2020 presidential candidate. O’Rourke’s pleas will fall on deaf ears unless Congress works on both sides of the aisle to fashion new federal laws to determine mental health histories of gun-buyers.