In the early hours of July 8, 2010, Scott Guy was gunned down at his farm gate. Police suspected his brother-in-law, but he was found not-guilty and no one else has been held accountable for the killing.

Thirty-one year old Scott Guy was on his way to work, it was just a regular day, when he was murdered in his driveway.

He had no known enemies and there were very few clues to point to who might have wanted him dead.

Eventually, police discovered there had been tensions between Guy and his brother-in-law Ewen Macdonald and that Macdonald had committed a string of other crimes in the neighbourhood.

They arrested him for murder, but he was found not-guilty.

Stuff Investigative journalist Mike White discusses why the police case against Ewen Macdonald failed and who else might have been responsible for Scott Guy's murder.

Go to this episode on rnz.co.nz for more details