A North Carolina prosecutor best known for trying Michael Peterson's infamous 2003 murder trial featured on Netflix's The Staircase documentary has died, marking the second death of a show participant since the miniseries premiered in June.

Freda Black, a former Durham County assistant district attorney, was found dead in her home on Monday, AEST time, Durham Police spokesperson Wil Glenn told USA Today.

Glenn said the 57-year-old's body has been sent to the State Medical Examiner for an autopsy, but her death "does not appear suspicious at this time".

Authorities were alerted to Black's home by loved ones who grew concerned after not being able to reach her.