Both authors talked at Emerald library this month and shared insights from the seedier side of life.

Jackson said she had never feared for her life while profiling two notorious murderers - Ivan Milat and Carl Williams.

She interviewed, wrote to and received letters from eight criminals, their families and friends for her book Inside their Minds: Australian Criminals.

The former television producer and investigative journalist for Today Tonight is the daughter of former chief superintendent Bill Jackson, whose police district ran from Dandenong to Pakenham.

Jackson, who exchanged letters with the late Williams, described him as an "absolute joker".

"At the end of his letters, he liked to share sayings such as, 'Life isn't about waiting for a storm to pass, but about dancing in the rain'.

"Ivan Milat always signed his letters off with an angel with a halo and under that he'd write 'innocent'.

For her book, Jackson worked with leading forensic psychologist Ian Joblin, who interviewed and accessed the criminals.

Martin, author of Body Count or Kiss of Death, with a heroine to die for - Australian FBI profiler Sophie Anderson - discussed how she wrote her novels.

"Even though I'm writing fiction, there's a lot of research to be done into forensic and police procedures," she said.