During the early 1990s, the most violent period in San Diego’s recent history, more people were murdered in San Diego than in Tijuana, its cross-border neighbor.
Just a fence separate the two cities, but the latest annual crime totals illustrate how public safety has grown worlds apart since then. San Diego had 29 murders last year — its lowest number since 1968 — while Tijuana reported 688.
Researchers have a wide range of theories about why crime has continued dropping in American cities since the 1990s despite the recent economic slump. They point to steeper prison sentences, changing demographics and greater access to social programs, to name a few.
Tijuana, however, has grown increasingly violent. Murders there have spiked since 2006, when President Felipe Calderon took office and intensified the Mexican government’s campaign to dismantle powerful drug cartels.
Using murder statistics from San Diego police, Baja California law enforcement authorities and Harvard scholar Viridiana Rios, who researches crime in Mexico, I created the illustration below. Tijuana had about 400,000 fewer residents than San Diego in 1990, but the cities are similar sizes today.

Please contact Keegan Kyle directly at keegan.kyle@voiceofsandiego.org or 619.550.5668 and follow him on Twitter: twitter.com/keegankyle.