On January 17, 1989, a gunman in Stockton, California walked onto a playground and opened fire, killing 5 children and injuring 30 more.
On July 1, 1993, a gunman in San Francisco walked into a law office and opened fire, killing 8 and injuring 6.
On April 20, 1999, two gunmen in Columbine, Colorado walked into their high school and opened fire, killing 13 people and injuring 21 others.
On January 16, 2002, a gunman ...