In December 2001, novelist Michael Peterson called to report that his wife Kathleen had fallen down a set of stairs and died. The authorities disbelieved Peterson’s story that Kathleen had fallen while drunk and concluded instead that Peterson had bludgeoned her to death, most likely with a fireplace poker which was discovered missing from the house.
*** WARNING: SPOILERS AHEAD ***
Peterson was soon charged with murder and the film details the ensuing case from the point of view of Peterson and his defense team. During the trial it is discovered that while Peterson was living in Germany a family friend of his died from an intra-cerebral haemorrhage followed by the body falling down stairs after collapsing which resulted in similar head injuries to those sustained by Peterson’s wife.
An investigation by German police and US military authorities concluded that the death was accidental and Peterson ended up adopting the woman’s two daughters. The prosecution introduced this death into the trial as an incident giving Peterson the idea of how to “fake” Kathleen’s accident. During the trial, Peterson’s daughters stand steadfastly by their father. The prosecution argues that Kathleen had discovered that Michael was bisexual and had been having affairs with men, which led to an argument where he bludgeoned her to death.
Peterson claimed that his wife knew about his sexuality and that they had an open marriage. He claims to have been outside by their pool when Kathleen fell down the stairs and injured herself. A defense team recreation shows that it would have been possible for Peterson to have missed his wife’s cries for help had he been by the pool. The jury ultimately convicts Peterson.