Understanding TCC and online radicalization to violence
When our analysis of TCC goes viral within TCC, we see a direct feedback loop that can reach members and help prevent future violence.
On Tuesday (3/24), a 15-year-old student entered the private Anton Makarenko High School, in the Mexican coastal municipality of Lázaro Cárdenas, Michoacán, and killed two of his female teachers.
Nine hours before the attack, he recorded himself in front of a mirror dressed in black and holding an AR-15 rifle. He posted on social media “Today is the day” and then shared a video on Instagram with references to hatred toward women and idolizing school shootings.
The teenager is the stepson of a Mexican Navy serviceman and the weapon he used was issued by the military (the AR belonged to another unidentified service member, not his stepfather).
The content he shared is associated with the “incel” universe, a digital subculture made up of men who call themselves “involuntary celibates” and post hateful content about women and feminism. Online radicalization of teens in Mexico isn’t new. Last October, a 19-year-old student, murdered a classmate at the College of Sciences and Humanities in Mexico City after posting his plan in incel groups online.
When teens become involved with extremist content online, there are different groups with different content, goals, and distinct subcultures. The warning signs, usernames, images, memes, and engagement style within each of these groups are different:
764 (article by Allizandra Herberhold)
If this wasn’t confusing enough, many teens who commit violence post content and interact with users across multiple groups.
Inside Online Radicalization
A recent episode of my podcast unexpectedly went viral within the online True Crime Community (TCC). TCC is a loosely connected network of social media users who share memes, fan art, live streams, and discussions centered around mass shooters and violent incidents.
This happened after TCC users searched the topic online, discovered the podcast, and circulated Allizandra Herberhold’s public LinkedIn profile on Tumblr. Some of the comments were criticism and accusations that we were attacking their community. Others were shocked that adults understood them and they reached out to Allizandra for help.
To better understand what TCC is, Allizandra Herberhold describes three rough levels of participation:
Romanticizers: people who find perpetrators attractive or are fascinated with them.
Idolizers: those who admire the violence or mythology around attacks.
Identifiers: the smallest but most dangerous group who personally identify with attackers and may move toward violence.
Most members are not violent and are more at risk of self-harm, isolation, or exploitation than committing attacks. Platforms like Tumblr and LinkedIn allow content to spread permanently through reposting and indexing. Algorithmic media also amplifies niche communities and make fringe spaces more visible and interconnected than in the past.
The internet enables isolated individuals in small communities to connect with others who share violent interests. Exposure to gore content, violent media, and shooter lore can desensitize individuals and reinforce radicalization. On our podcast, Allizandra and I discussed the connections between these online dynamics in recent cases like the Apalachee school shooting in Georgia where warning signs (online threats and fixation on past shooters) were missed by police during an interview at the shooter’s home months before the attack.
Georgia school shooter police interview: Same failures as Ohio in February
“God forbid if I didn’t do my job and something happened, I’d feel pretty bad about it.”
Allizandra and I argue that better Behavioral Threat Assessment and Management (BTAM) training, including a new Stoplight Model, could help authorities recognize warning signs and intervene earlier. On the flip side, zero-tolerance responses can worsen radicalization by pushing vulnerable youth deeper into online communities because they no longer have a offline community when they are expelled from in-person classes. Effective prevention needs to focus on building trust and reconnecting youths with real-world, human support systems.
If you don’t have the time or interest in watching us talk for an hour, here is a summary of the key points:
1. Podcast Content Went Viral in the TCC Community
The podcast episode discussing the True Crime Community (TCC) began circulating within TCC spaces online.
Alexandra discovered this after seeing her LinkedIn profile shared on Tumblr, where users criticized her posts and accused her of attacking their community.
The visibility occurred because LinkedIn posts are publicly indexed in search results, allowing TCC members to easily find and discuss the hosts.
2. Structure and Behavior of the TCC Online Community
TCC functions similarly to a fandom-style online community with memes, edits, jokes, and aestheticized content about perpetrators.
Alexandra describes three rough levels of participation:
Romanticizers – people who find perpetrators attractive or are fascinated with them.
Idolizers – those who admire the violence or mythology around attacks.
Identifiers – the smallest but most dangerous group who personally identify with attackers and may move toward violence.
Most members are not violent and are more at risk of self-harm, isolation, or exploitation than committing attacks.
3. Social Media and Algorithmic Visibility
Platforms like Tumblr and LinkedIn allow content to spread permanently through reposting and indexing.
Algorithmic media ecosystems amplify niche communities and make fringe spaces more visible and interconnected than in the past.
4. Case Study: Apalachee School Shooting
The discussion examines the Georgia school shooting case involving a 14-year-old attacker whose father bought him an AR-15.
The father faces manslaughter and multiple felony charges for allowing access to the weapon despite warning signs.
Evidence revealed the shooter had photos of previous perpetrators on his bedroom wall, indicating potential radicalization.
A prior tip to police about threats posted online led officers to visit the home.
The officers conducted a poorly executed interview, dismissed warning signs as “boys being boys,” and failed to investigate further.
The hosts argue that better training in threat assessment and interviewing could have prevented the attack.
5. Role of Online Radicalization & International Spread of TCC Ideology
The internet enables isolated individuals in small communities to connect with others who share violent interests.
Exposure to gore content, violent media, and shooter lore can desensitize individuals and reinforce radicalization.
TCC culture has spread globally; examples include Indonesia, Europe, Russia, and Latin America.
In Indonesia, authorities arrested 112 students linked to TCC activity, including 20 viable school shooting plots.
International participants often adapt American shooter mythology and symbolism.
6. Importance of Behavioral Threat Assessment (BTAM)
The hosts emphasize the need for BTAM training for police and schools to properly interpret warning signs and online leakage.
Zero-tolerance discipline policies can backfire by isolating youth and increasing grievance, potentially pushing them further toward radicalization.
Indicators that may signal escalation toward violence include:
Increasing fixation on perpetrators
Access to firearms
Threats or violent posts online
Behavioral changes or withdrawal
Attempts to hide activity (e.g., switching from digital posts to handwritten journals)
Many perpetrators exhibit suicidal ideation or social isolation.
The hosts argue mass violence can often resemble violent public suicide, emphasizing the need for mental health intervention.
7. Deradicalization Approaches and Message to TCC Members
Effective intervention focuses on behavioral change rather than ideology:
Reducing time spent in extremist online spaces
Rebuilding real-world connections
Helping youth reach life milestones (school, jobs, social activities)
Building trust and showing they are not abandoned or judged
Alexandra encourages members of TCC who want to leave the community to seek help without fear of judgment.
The hosts emphasize that young people involved in these spaces can still be redirected before violence occurs.
Prevention requires support, education, and engagement rather than purely punitive responses.
What can we do to notice and de-escalate online radicalization? Here is a new “Stoplight Model” tool that’s meant to be informational and used in conjunction with other BTAM models. Think of it as an enhancement for more easily identifying what is a threat (or what may not be at threat) when assessing someone identified as a possible member of TCC.
This tool is meant to be informational and used in conjunction with other BTAM models. After reading that summary, hopefully you want to listen to everything we have done on this topic!
Ep 60. Inside the True Crime Community (TCC) that grooms teens into school shooters. The last 7 school shooters were all connected with the same online group that shares violent gore content, fan art idolizing prior school shooters, and encourages members to commit real-world violence
Ep 57. TCC, gore videos, groypers, and online radicalization
112 TCC-radicalized students identified by police in Jakarta, Indonesia
David Riedman, PhD is the creator of the K-12 School Shooting Database, Chief Data Officer at a global risk management firm, and a tenure-track professor. Listen to my podcast—Riedman Report: Risk, AI, Education & Security—or my interviews on Freakonomics Radio and the New England Journal of Medicine.
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