Since this show is getting compared to Netflix's Making of a Murderer, FWIW, this series was not produced by Netflix. It was produced and released independently by French filmmaker Jean-Xavier de Lestrade and originally came out in 2004, with new episodes added later. This series is widely well-regarded by do entary fans, and it has won a Peabody award.
Jean-Xavier de Lestrade also made this do entary, Murder On a Sunday Morning, which won an Oscar for best do entary. If you found Making of a Murderer & The Staircase interesting, I highly recommend this film.