JCS – Criminal Psychology, also known as Jim Can't Swim, is a true crime YouTube channel that is known to upload long and in-depth video analyses of police interrogations and criminal cases.
JCS is considered by sources like "Vice" and "Screen Rant" to be one of the best and most popular channels in terms of true crime content on the Internet. The channel has 5.5 million subscribers since its creation in 2017 and uploads 1–2 videos a year.
History.
The channel of JCS was registered in 2017, it was mostly inactive, and only appeared on Patreon. Two years later, in 2019, the channel started being active again. The identity of the person who runs the channel is unknown. Some said that the channel is a work of a group of people.
In 2019, the channel uploaded video analyses of several crimes, like Watts family murders and Russell Williams case. In 2020, the channel uploaded another video titled "Wrath of Jodi", which discussed Jodi Arias, a woman who murdered her boyfriend. It was 2 hours long and was considered to be longest on the channel. The channel uploaded its first popular video on May 26, 2021, titled “What pretending to be crazy looks like”. The video was hour-long and explained the psychology of Nikolas Cruz, perpetrator of Parkland high school shooting. The video also analyzed other criminals, like Jerrod Murray, a man who murdered his classmate and Dawson McGee, a man who murdered his mother. The video would receive over 42 million views and become the biggest on the channel. Some experts from "Vice" said it was boosted by YouTube's algorithm due to its length and quality. Later, the video became a meme, after various social media users started asking why they were recommended it. Shortly after that, JCS rose in popularity, gaining over 3.64 million subscribers and over 210 million views. JCS was considered to be one of the most popular true crime channels on the internet, with streamers like Valkyrae, xQc, Hasan Piker and others co-streaming JCS's videos.
On January 2022, many JCS videos were taken down for "violent and graphic content", and the channel also received a strike. Despite requests from his community, JCS never reinstated the removed videos. Later, the channel announced plans to abandon YouTube and move to a different platform. However, on January 19, 2022, a group of four YouTube moderators reviewed the videos and reinstated them. JCS thanked them and confirmed the channel would continue using YouTube.
On April 2025, after taking a long break from uploading videos, JCS uploaded a new video, titled: "Newlyweds tell on each other". The video was heavily criticized by the community for its low quality, with some accusing it of using AI narration instead of the voice of Kizzume, a YouTuber who narrated JCS's videos. Some members of the community suspected that the channel of JCS was sold to a new team. JCS would apologize in the comment section of another video, stating: "Sorry for letting you guys down... The channel wasn't sold, and we haven't quit. We just been dealing with some outside YouTube-related stuff". On June 4, 2025, JCS released a new video, titled: "Amber’s Afternoon" which received almost 900k views in 15 hours. Dexerto reported that multiple Reddit users criticised the video for being low quality and that a few suspected AI was used somewhere in production.
Content.
JCS's videos mostly consist of explaining interrogation techniques, body language cues, and psychological torture used by law enforcement against the suspects. During the videos, he adds his own commentary about interrogated suspect's mental conditions. JCS also adds his own opinions and jokes in the videos. Reportedly, videos of JCS has inspired "a movement" within YouTube's true crime genre, with many other true crime channels copying his techniques. 
The voice-over in JCS's videos is narrated by Kizzume, a YouTuber whose voice was described as "soothing but compelling" by "Vice" staff. JCS takes long breaks between the videos, uploading approximately two videos a year; the length of the videos varies from 13 minutes to around two hours. The videos were described by critics as high quality and well researched.