Scrawled messages on bullet casings and weapons left behind have popped up at several high-profile shootings over the past year. The seemingly unusual practice is actually reminiscent of a centuries-old tactic but can often provide insight to investigators.

From the fatal 2024 ambush of UnitedHealthCare CEO Brian Thompson to the August attack on a Minneapolis Catholic school, plus deadly shootings this month of conservative activist Charlie Kirk and people at a Dallas immigration facility, each gunman inscribed messages on their ammunition and firearms depicting cultural and political ideologies.

Experts say while the micro-trend is alarming, in some instances it’s revealing for detectives parsing through crime scenes for a potential motive. And while performative in nature, suspected extremists want to ensure their point is made, controlling the narrative even if they aren’t alive to see it or are on the run from law enforcement.

Here’s a look at how the practice has evolved and what we can interpret from the messages left behind.

‘Psychological warfare’

Early warfare focused on hand-to-hand combat, but in time, the types of weapons advanced to include items like slings, crossbows and swords and with them came the practice of sending messages with their use.

Inscriptions on weapons and ammunition alike take on three categories: personalization for the o