My brain made me do it

March 9, 2026·27 min·2 clips

A PET scan revealed an orange-sized cyst pressing on Herbert Weinstein's frontal lobe after he confessed to strangling his wife.

Host Amy Padula opens in 1991 with retired ad executive Herbert Weinstein, 65, strangling his wife Barbara in their Manhattan apartment and staging a suicide by pushing her body from their 12th-story window. Police arriving on the scene found him in the lobby acting oddly unconcerned and noticed a scratch on his face and a bloodied hand before he confessed. His defense attorney, struck by how calm Weinstein was, ordered a psychiatric evaluation and a PET scan, which revealed an orange-sized arachnoid cyst pressing on his frontal lobe. In the People v. Weinstein trial, a judge allowed a PET scan into evidence for the first time in the United States. Ethics professor Josh May and Stanford neuroscientist Anthony Wagner describe the cyst as a cerebral-spinal-fluid-filled sac that can impinge on underlying brain tissue and, in a small share of cases, change behaviour. Wagner outlines the role of the lateral prefrontal cortex in representing goals and producing context-appropriate behaviour, using the example of someone with frontal damage answering a phone in a doctor's office. The episode explains the Frye and Daubert standards for admitting scientific evidence and the pretrial hearings that decide what juries may see. Judge Richard Carruthers allowed the scan in October 1992 but barred experts from explicitly saying the cyst caused violence. Fearing the scan would sway the jury, prosecutors offered a deal the morning of jury selection, letting Weinstein plead guilty to manslaughter and receive seven to twenty-one years. Weinstein never had the cyst removed and reportedly showed no violence in over twelve years of incarceration. The episode traces how the case opened neuroimaging into the American legal system, including the 2005 Roper v. Simmons Supreme Court ruling that cited adolescent brain research to overturn the juvenile death penalty. Philosopher of neuroscience Adina Roskies explains that science tends to produce population-level generalisations, whereas the law must judge individual acts. Josh May argues that other admitted evidence like eyewitness testimony is also unreliable and that juries need more, not less, information. The episode then surveys how fMRI replaced PET as the workhorse of human neuroscience in the 1990s and how it is now combined with AI tools to decode brain patterns. Anthony Wagner notes the MacArthur Foundation review of brain-based lie detection and concludes the field is not ready for courtroom use. The episode closes on open philosophical questions about agency, consciousness, and whether we are our brains, and points to Kevin Davis's book The Brain Defense for more.

As heard by us

A brain scan becomes a question about blame, control, and how far evidence can reach.

Unexplainable turns a 1991 Manhattan case into something more uneasy than tidy true crime: a scan shows a cyst pressing on the frontal lobe, and the show keeps asking how much control a person really has when the brain itself is part of the argument.

Read the full review in PlayNext →

Why you'd press play

If you want neuroscience tangled up with culpability, this is the one.

Read the full recommendation in PlayNext →

Listen to the show on

Apple Podcasts Spotify

Play clips from this episode More from Unexplainable