The lawyer for a Kentucky man accused of strangling his wife argued at trial Monday that excessive caffeine from sodas, energy drinks and diet pills left the defendant so sleep-deprived and mentally unstable that he falsely confessed to the killing.

Attorney Shannon Sexton said in opening statements at the murder trial of Woody Will Smith, 33, that he did not kill his 28-year-old wife, Amanda Hornsby-Smith, on May 4, 2009. The lawyer also told jurors that the man’s statements to police were made under high stress prompted by large amounts of caffeine and a lack of sleep.