Virginia State Police will be required to offer voluntary criminal background checks at gun shows under a new law that goes into effect Friday.

WASHINGTON — Virginia State Police will be required to offer voluntary criminal background checks at gun shows under a new law that goes into effect Friday.

The law, passed by the General Assembly this year, allows private gun sellers to immediately request a background check on a potential buyer. Previously, only federally-licensed gun dealers were able to request such a check.

“A background check in a private sale ensures that the gun is transferred only to a person lawfully eligible to possess firearms and provides evidence to the seller of diligence to protect against the illegal transfer of firearms,” reads a statement from Virginia State Police.

The law requires members of Virginia State Police to be available at every gun show statewide to conduct the checks and determine whether prospective buyers are prohibited from owning a firearm under state or federal law.

Background checks will take about three minutes to complete, and they will cost $2.

“Participation in these background checks is strictly optional and based upon agreement entered into by the firearms seller and recipient,” the statement reads.

The gun show measure is part of a series of gun-related laws taking effect Friday.

Under other new laws, more out-of-state concealed-handgun permit holders will be able to legally carry guns in Virginia, and people subject to permanent protective orders will be barred from carrying firearms.

The Associated Press contributed to this report.