
Detective Mark Lounsbury with the local police had testified that Amero had intentionally surfed to the porn website.
The defence by contrast argued that the images were served up by adware and spyware applications that had infected the computer.
In overturning the previous ruling, judge Judge Hillary Strackbein dimissed Lounsbury's testimony as "erroneous".
"The jury may have relied, at least in part, on that false information," Strackbein ruled according to the Norwich Bulletin, a local news paper.
"[Amero] is entitled to a new trial in the interest of justice."
The case has made big waves on computer security blogs for the apparent lack of computer knowledge with the judge and police witnesses. Both Sunbelt and the VitalSecurity blog for have pleaded that Amero couldn’t be held accountable for software that operated outside of her control and without her consent.
Amero was originally scheduled for sentencing on Wednesday. Instead she entered another not guilty plea.