This law imposes a waiting period of ten days between the purchase of a firearm and when the buyer can take possession of it. When estimating the effects of this law, experts were asked to assume that the state already has a universal background check requirement. Read our analysis of this type of policy

This policy specifically allows school personnel—other than peace officers—to carry firearms on school property. Staff members authorized to carry firearms are required to undertake at least 40 hours of initial training that covers use of force, weapon proficiency, the law, and first aid. Read our analysis of this type of policy

This law bans certain semi-automatic firearms with detachable magazines and other features, such as pistol grips, folding stocks, or the ability to mount a bayonet. The law also bans magazines that hold more than 15 rounds of ammunition. Owners of these weapons at the time the law is passed may keep them if each weapon is registered with a state authority. Read our analysis of this type of policy

This law imposes criminal penalties on firearm owners when a child accesses a usable weapon that was stored in a location where the owner should have known a child could access it. Read our analysis of this type of policy

Federal and some state laws prohibit carrying a firearm near schools and certain other public places. This policy allows firearms in these previously prohibited locations. When estimating the effects of this law, experts were asked to assume that federal and state laws change in a state that previously prohibited private citizens from carrying firearms into schools, universities, government buildings, and parks. Read our analysis of this type of policy

When a judge has committed someone to an inpatient mental institution or has found the person to be unable to manage his or her own affairs, federal law prohibits that person from having firearms. This law expands the prohibition to include people ordered to receive outpatient mental health treatment and those involuntarily confined because a mental health professional determined that they present a danger to themselves or others. Read our analysis of this type of policy

This law authorizes police and family to request a court order prohibiting an individual deemed at imminent risk to themselves or others from possessing firearms, requiring him/her to temporarily relinquish all firearms to the police. The court can order the emergency removal of firearms for 14 days before any hearing at which the subject of the order has the opportunity to present evidence. Read our analysis of this type of policy

This policy imposes a special $25 tax on the sale of firearms and a 25% tax on the sale of ammunition. Read our analysis of this type of policy

This law prohibits individuals who are not licensed firearms dealers from purchasing more than one handgun within a 30-day period. All private and dealer sales are reported to a state agency that flags individuals who have purchased more than one handgun in a 30-day window. It is a crime for both seller and buyer to complete the sale if this check fails. All records of sales are destroyed after 60 days.

Firearm owners must report lost or stolen firearms to law enforcement authorities within seven days of discovering the loss. Penalties for failure to report include prohibition on firearm ownership for some period and possible civil liability if the firearm is used in a crime. Read our analysis of this type of policy

Federal law generally prohibits those younger than 18 from having a handgun, and licensed dealers are prohibited from selling firearms to anyone younger than 18. The minimum age requirement policy raises the minimum age for purchase or possession of any firearm to 21. Read our analysis of this type of policy

This policy allows anyone who is at least 21 years old and not prohibited by law from having a firearm to carry a concealed weapon in public without a permit. For the effect estimates, experts were asked to assume that, before adopting a permitless-carry policy, the state required concealed-carry permits that were issued to those with good moral character and sufficient reason to carry a concealed firearm. Read our analysis of this type of policy

This law prohibits gun possession by individuals subject to domestic violence restraining orders. Each restraining order requires the surrender of firearms to police for 14 days without giving the gun owner an opportunity to present evidence. Read our analysis of this type of policy

This law requires a firearm license to purchase or possess a firearm. These licenses require successful completion of a safety training course or safety test and a background check, and cost $100. They must be renewed every ten years. Read our analysis of this type of policy

This law requires reporting all firearm sales to a government agency, including information on the firearms and who bought them. This applies to sales by both firearm dealers and private sellers. Law enforcement is permitted to retain the data indefinitely for two purposes: to trace firearms found at crime scenes and to retrieve firearms from individuals who become prohibited possessors. Read our analysis of this type of policy

This law permits a person to use deadly force without the duty to retreat when confronting a threat that could reasonably result in death or serious injury. Without this law, people outside their homes must try to withdraw from a serious threat, if possible, before using deadly force. Read our analysis of this type of policy

This law criminalizes attempted purchase of firearms by individuals prohibited by law from possessing a firearm. It also funds personnel who are tasked exclusively with investigating and prosecuting prohibited possessors who make false statements on state or federal forms when attempting to acquire a firearm.

Under this law, when a judge's ruling places an individual in a class that is prohibited by law from possessing or purchasing a firearm, the judge must determine whether that individual has firearms and, if so, must order their surrender. Prohibited possessors include people convicted of a felony, those convicted of misdemeanor domestic violence, and those subject to a domestic violence protective order. Read our analysis of this type of policy

People who are prohibited by law from having firearms sometimes obtain them through private sales that do not require background checks. Universal background checks require background checks prior to all transfers of firearms, including private sales over the internet, at gun shows, and between friends (temporary loans and gifts between family members are exempted). Background checks for private sales are conducted by a government agency or by a licensed gun dealer. Read our analysis of this type of policy