The biggest shooting in U.S. history is the October 1, 2017 attack at the Route 91 Harvest country music festival in Las Vegas, where a gunman firing from a 32nd-floor suite at the Mandalay Bay Resort and Casino killed 60 people and injured more than 800 concertgoers over roughly 11 minutes. The shooter, 64-year-old Stephen Paddock, took his own life as police reached his room. The massacre triggered an $800 million civil settlement with the hotel’s owner, a short-lived federal ban on the accessories Paddock used to accelerate his fire, and renewed pressure on Congress that eventually produced the first significant federal gun safety law in nearly 30 years.
What Happened at Mandalay Bay
Paddock checked into a two-room suite several days before the attack and gradually brought in luggage that concealed firearms, ammunition, and surveillance equipment. He mounted two cameras on a room service cart in the hallway and connected them to laptops inside the suite, letting him watch for anyone approaching the door.
Investigators later recovered 24 firearms from the hotel rooms. At least 12 were AR-15-style semiautomatic rifles fitted with bump stocks, accessories that use a rifle’s recoil to fire at rates approaching those of fully automatic weapons. Also in the suite were roughly 1,050 spent shell casings and more than 5,200 rounds of live ammunition.1KTNV. List of Guns and Evidence From Las Vegas Shooter Stephen Paddock Another 25 firearms turned up at Paddock’s homes in Mesquite and Reno, Nevada, bringing the total recovered to 49.
At about 10:05 p.m., Paddock opened fire on a crowd of roughly 22,000 people across the street. Fifty-eight died during the shooting itself; two more victims died of shooting-related injuries in the years that followed, bringing the official death toll to 60.2CNN. Las Vegas 2017 Shooting Stephen Paddock Letters More than 800 others were injured, including 413 who sustained gunshot wounds requiring immediate treatment.3National Institutes of Health. Las Vegas Mass Casualty Incident
Why He Did It
The FBI closed its investigation in January 2019 without identifying a definitive motive. Agents found “no single or clear motivating factor” and determined Paddock was not driven by any religious, social, or political agenda.4NPR. FBI Finds No Motive in Las Vegas Shooting, Closes Investigation The bureau described a “complex merging” of stressors: a desire to die by suicide, deteriorating physical and mental health, and a goal of achieving notoriety through a mass casualty attack. No manifesto or suicide note was ever recovered.
Paddock, a retired postal worker, accountant, and real estate investor, had gone to unusual lengths throughout his life to keep his thoughts private. Later-released FBI documents showed he was a prolific video poker player who maintained a gambling bankroll of $2 to $3 million and wagered about $1 million per year. One interviewed gambler told agents Paddock may have “snapped” over resentment at changes in how casinos treated high rollers, and that he had been banned from three casinos in Reno.5CNN. Las Vegas 2017 Shooting Stephen Paddock FBI Documents The FBI and the Las Vegas Metropolitan Police Department both concluded Paddock acted alone.
The MGM Settlement
Victims and their families filed a class-action lawsuit against MGM Resorts International, alleging the hotel operator was negligent in allowing Paddock to move an arsenal of weapons and thousands of rounds of ammunition through its property in more than 20 heavy bags over several days.6NPR. MGM Resorts to Pay Up to $800 Million to Victims of Las Vegas Shooting MGM initially tried to defeat the claims by countersuing victims under a post-9/11 federal law regarding anti-terrorism security technology.
In October 2019, MGM agreed to a settlement of between $735 million and $800 million. A judge approved the final $800 million figure in September 2020, with funds distributed among more than 4,000 claimants by a pair of retired judges.7CNN. Las Vegas Shooting Settlement Approved MGM itself paid $49 million; the remaining $751 million came from its liability insurers. The settlement was not an admission of wrongdoing.
The Bump Stock Ban and Its Reversal
The Las Vegas attack drew immediate national attention to bump stocks. In 2018, the Bureau of Alcohol, Tobacco, Firearms and Explosives issued a rule under the Trump administration classifying them as “machineguns” under federal law, effectively banning possession and requiring owners to destroy or surrender the devices.8SCOTUSblog. Supreme Court Strikes Down Bump Stock Ban
Michael Cargill, a Texas gun shop owner who surrendered his bump stocks under the rule, challenged it in federal court. The case, Garland v. Cargill, reached the Supreme Court, which ruled 6-3 on June 14, 2024 that the ATF had exceeded its statutory authority. Writing for the majority, Justice Clarence Thomas concluded that a semiautomatic rifle equipped with a bump stock does not meet the statutory definition of a machinegun. The trigger still resets between each shot, he wrote, and firing requires the shooter to maintain constant forward pressure, meaning the weapon does not fire “automatically.”9U.S. Supreme Court. Garland v. Cargill, No. 22-976
Justice Sonia Sotomayor, joined by Justices Kagan and Jackson, dissented sharply, arguing the majority’s interpretation “resists” the ordinary meaning of the statute and warning the decision “will have deadly consequences.” Justice Alito, concurring with the majority, noted Congress could amend the law to explicitly cover bump stocks if it chose to. Congress has not done so; a Senate vote to ban bump stocks failed after the ruling.10Tennessee Lookout. U.S. Supreme Court Overturns Ban on Bump Stocks Used in Las Vegas Mass Shooting Over a dozen states maintain their own bans on the accessories.11NBC News. Supreme Court Rules Gun Bump Stocks Ban Unlawful
How Las Vegas Compares to Other Deadliest U.S. Shootings
Las Vegas stands alone at the top of the modern record, but a handful of other attacks form the rest of the list most often cited.
Pulse Nightclub (2016) — 49 Killed
Before Las Vegas, the June 12, 2016 attack on the Pulse nightclub in Orlando, Florida was the deadliest mass shooting in modern U.S. history. Omar Mir Seddique Mateen, a 29-year-old U.S. citizen, entered the club with a Sig Sauer MCX semiautomatic rifle and a Glock 17 pistol, both purchased legally that month.12Britannica. Orlando Shooting of 2016 He killed 49 people and wounded at least 53 before being shot and killed by police around 5:00 a.m. During the attack, Mateen made three 911 calls claiming allegiance to the leader of ISIL. The FBI classified the attack as an act of terrorism.13FBI. Pulse Nightclub Shooting President Barack Obama characterized it as both terrorism and a hate crime targeting the LGBTQ community.
Virginia Tech (2007) — 32 Killed
On April 16, 2007, Seung-Hui Cho, a Virginia Tech senior with a documented history of mental illness, killed 32 people and wounded 17 others in two attacks on campus before taking his own life. University officials did not send a campus-wide alert for roughly two hours after the first shooting in a dormitory, during which Cho moved to Norris Hall and carried out the deadlier second attack.14NBC News. Virginia Tech Shooting Settlement Virginia reached an $11 million settlement with most victims’ families in 2008. Two families that opted out sued for negligence and initially won $4 million each, but the Virginia Supreme Court dismissed the case in October 2013, ruling the shooting was not “reasonably foreseeable” and the university had no duty to warn students of potential criminal acts by a third party.15CNN. Virginia Tech Shooting Negligence Lawsuit At the federal level, Congress passed the NICS Improvement Amendments Act of 2007, incentivizing states to share mental health records with the national background check system.16Britannica. Virginia Tech Shooting
Sandy Hook (2012) — 26 Killed
On December 14, 2012, a gunman killed 20 first-graders and six adults at Sandy Hook Elementary School in Newtown, Connecticut. The shooting’s legal legacy has been enormous. In February 2022, the families of nine victims reached a $73 million settlement with Remington Arms, the manufacturer of the AR-15-style rifle used in the attack. The families sued under Connecticut’s Unfair Trade Practices Act, alleging Remington recklessly marketed assault weapons to civilians.17NPR. Sandy Hook Victims Families Settlement Remington The $73 million represented the full available insurance coverage of Remington’s four insurers; the company itself had filed for bankruptcy in 2020. The deal was widely seen as the first significant damages award against a gun manufacturer in a mass shooting case, breaking through the broad legal shield provided by the Protection of Lawful Commerce in Arms Act.18New York Times. Sandy Hook Families Settlement
Sutherland Springs (2017) — 26 Killed
On November 5, 2017, barely a month after Las Vegas, a gunman killed 26 people and injured 20 at the First Baptist Church in Sutherland Springs, Texas. The shooter had a 2012 domestic violence conviction from his time in the U.S. Air Force that should have disqualified him from buying firearms, but the Air Force never reported the conviction to the National Instant Criminal Background Check System. A district judge found the Air Force 60% liable and ordered $230 million in damages.19Texas Tribune. Sutherland Springs Lawsuit Air Force The Department of Justice appealed but tentatively agreed to a $144.5 million settlement in April 2023.20NPR. DOJ Sutherland Springs Settlement Mass Shooting
El Paso (2019) — 23 Killed
On August 3, 2019, Patrick Wood Crusius opened fire at a Walmart in El Paso, Texas, killing 23 people and wounding 22. Crusius admitted targeting victims based on their actual or perceived Hispanic national origin and had published a white nationalist manifesto before the attack.21U.S. Department of Justice. Texas Man Pleads Guilty to 90 Federal Hate Crimes and Firearms Violations In February 2023, he pleaded guilty in federal court to 90 counts, including 45 hate crime charges, and was sentenced to 90 consecutive life terms. He also agreed to pay more than $5 million in restitution.22CNN. Patrick Crusius Plea Deal El Paso Walmart In April 2025, Crusius pleaded guilty in state court to capital murder and received an additional life sentence without parole.23El Paso Matters. Patrick Crusius Guilty, Life in Prison Sentence
Uvalde (2022) — 21 Killed
On May 24, 2022, a gunman killed 19 students and two teachers at Robb Elementary School in Uvalde, Texas. A January 2024 Department of Justice critical incident review called the law enforcement response a “failure.” Officers retreated after initial gunfire and treated the situation as a barricaded-subject scenario rather than an active shooter event, producing a 77-minute gap before anyone confronted the gunman while 33 students and three teachers remained trapped with him.24U.S. Department of Justice. Justice Department Releases Report on Critical Incident Review of Robb Elementary Former school district police chief Pete Arredondo and former officer Adrian Gonzales were indicted on felony charges of child endangerment, the first criminal charges against any officers involved in a mass shooting response.
Parkland (2018) — 17 Killed
On February 14, 2018, Nikolas Cruz killed 14 students and three staff members at Marjory Stoneman Douglas High School in Parkland, Florida. Cruz pleaded guilty to 17 counts of murder and 17 counts of attempted murder. In October 2022, the penalty phase jury could not unanimously recommend death, with three jurors citing mitigating factors including neurodevelopmental disorders tied to fetal alcohol syndrome, and Cruz was sentenced to life without parole.25CNN. Parkland Shooter Nikolas Cruz Sentencing
The Federal Legislative Response
Despite the scale of repeated mass shootings, Congress went nearly 30 years without passing major gun safety legislation. That changed in June 2022, when President Biden signed the Bipartisan Safer Communities Act into law in the wake of Uvalde. The law requires enhanced background check procedures for firearm purchasers under 21, giving the FBI up to ten business days to review juvenile and mental health records. It establishes federal criminal statutes for firearms trafficking and straw purchasing, and it closes the so-called “boyfriend loophole” by prohibiting individuals convicted of domestic violence against a dating partner from possessing firearms for five years.26U.S. Senator John Cornyn. Bipartisan Safer Communities Act
The law also funds state crisis intervention programs, including extreme risk protection orders (commonly called red flag laws), and invests $250 million over five years in community violence intervention. It does not create a federal red flag law and does not impose new mandatory waiting periods.27Giffords Law Center. Bipartisan Safer Communities Act The enhanced background check provisions for buyers under 21 are set to expire in 2032.
Red Flag Laws by State
As of 2026, 22 states, the District of Columbia, and the U.S. Virgin Islands have enacted extreme risk protection order laws, with Maine the most recent in 2026.28Johns Hopkins Center for Gun Violence Solutions. Red Flag Laws or ERPOs These civil court orders allow temporary removal of firearms from individuals deemed at high risk of harming themselves or others. A Connecticut study found roughly one suicide prevented for every 17 to 23 orders issued, and an analysis of nearly 6,800 cases across six states found that 10% were issued in response to threats of mass shootings targeting three or more people.29RAND Corporation. Extreme Risk Protection Orders Whether ERPOs have measurably reduced mass shootings remains, by RAND’s assessment, inconclusive.
Gun Manufacturer Liability After Sandy Hook
The Protection of Lawful Commerce in Arms Act, signed in 2005, gives the firearms industry broad immunity from civil liability when its products are used in crimes. The law generally bars lawsuits resulting from the “criminal or unlawful misuse” of firearms, though it includes six exceptions, including cases where a manufacturer or seller knowingly violated a state or federal statute related to the sale or marketing of a product.30Giffords Law Center. Gun Industry Accountability
The Sandy Hook families’ Remington settlement exploited this opening by suing under Connecticut’s consumer protection law rather than traditional product liability. That result energized similar litigation across the country. Ten states — California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Maryland, New Jersey, New York, and Washington — have since enacted firearm industry responsibility laws designed to fit within PLCAA’s exceptions. Lawsuits tied to the Uvalde, Highland Park, and King Soopers shootings, among others, are testing these frameworks.