He is known for his work as a filmmaker and journalist who has produced several documentaries, but he has not directed any.
He has worked on films like:
* The Jinx: The Life and Deaths of Robert Durst (2015): A six-part documentary series that investigated the life of Robert Durst, a wealthy real estate heir suspected of multiple murders. Johnson was the executive producer.
* The Staircase (2004): A documentary series about Michael Peterson, a writer accused of murdering his wife. Johnson was the executive producer and co-director of the first season.
It's easy to get confused since he's been very involved in the production and development of these documentaries, but he hasn't taken the directorial credit.