Between August 1991 to January 1992, he shot eleven people in the Stockholm and Uppsala area, most of whom were immigrants, killing one and seriously injuring the others.

According to newspaper reports, he was bullied as a child because of his non-Swedish background, which manifested in him being teased for having very black hair and brown eyes.

Ausonius developed a hatred for Communists, Social Democrats, and immigrants while craving an ambition of gaining wealth.

His talent for the market quickly earned him a fairly large fortune, resulting in him adopting the yuppie lifestyle.

He sawed off the barrel and the stock of his first rifle to make it shorter, and he fitted the Smith & Wesson revolver with a silencer.

On all three occasions the National Board of Forensic Medicine determined that there was a risk that Ausonius would re-offend due to his autism and personality disorder, which the court took into consideration when making its decision.

[7] In 2016 Ausonius was extradited to Germany to face trial for the 23 February 1992 murder in Frankfurt of Blanka Zmigrod, a 68-year-old Holocaust survivor.

While investigating, German police looked into ties to far-right terror group National Socialist Underground.

Prosecutors had charged him with stealing her handbag after killing her because he thought she had taken an electronic device that he used to save his bank account numbers.

[13] The journalist Gellert Tamas wrote a book about the case, Lasermannen – en berättelse om Sverige (2002), which became a bestseller.

[14] In 2005, the book was adapted into a play, and the same year SVT produced a three-part TV miniseries, which premiered on 23 November.

In late April 2006, the daily Aftonbladet revealed that John Ausonius had become engaged to an anonymous 23-year-old woman, who had fallen in love with him after having seen a recent television miniseries.

[15] According to the paper, a friend of the woman said the couple were planning to move abroad after Ausonius' putative release from prison by 2031.