Washington state voters on Tuesday approved initiative 1639 with 60 percent of the vote, significantly strengthening the state’s firearm laws.

The measure will raise the legal age to buy semiautomatic rifles from 18 to 21. To obtain such firearms, potential gun owners will need to pass an enhanced background check, show proof that they completed a safety training course and wait 10 business days after an application to purchase. Additionally, the measure enacts a new storage law that requires all gun owners to secure their firearms, or risk criminal penalties.

Safe Schools Safe Communities was registered to support this initiative and reported a total of 5.49 million in contributions. Paul Allen, the co-founder of Microsoft, was the top donor, contributing a total of 1.25 million.

The initiative aims to increase public safety for all Washingtonians, in particular the state’s children.

The impacts of gun violence by assault weapons fall heavily on children and teenagers. According to one analysis, more than two hundred eight thousand students attending at least two hundred twelve schools have experienced a shooting on campus since the Columbine mass shooting in 1999…Enough is enough. The people find and declare that it is crucial and urgent to pass laws to increase public safety and reduce gun violence.

The ballot has been subject to three lawsuits, but the Washington Supreme Court allowed the initiative to stay on the November 2018 ballot.