An American writer who penned a piece called How To Murder Your Husband is on trial for murdering her husband.

Novelist Nancy Crampton Brophy, whose Wrong Never Felt So Right books include The Wrong Husband, is accused of killing her husband Daniel with a gun whose now-missing barrel she bought on eBay.

According to the police, the 71-year-old struggled to pay her mortgage but kept up 10 separate life insurance policies on her husband.

At the same time, the author has been picking holes in the prosecution case, saying: "I think you need to work harder on this story, you have a big hole in it."

CCTV cameras caught her close to the murder scene.