The show, which featured a storyline about bullying in the army, was criticised by a veteran of the 2003 Iraq War last week and General Sir Peter Wall, the head of the army, unsuccessfully called on the BBC to pull the episode.
The Guardian reports that General Sir Richard Dannatt, the former head of the army, also complained about the show during an appearance on Radio 4's Today programme this morning.
Dannatt claimed that the episode was "nasty" and accused the BBC of "gross arrogance" and a "gross error of editorial judgement".
He added that it "portrayed bullying that's got no place in fact or fiction in the 21st century" and said: "BBC One stands indicted for gross insensitivity while the army's conducting difficult and dangerous operations in Afghanistan."
However, the BBC's director of vision Jana Bennett, who was also on the Today programme, described the episode of Accused as "thought-provoking".
"This isn't in any way a docudrama or a documentary, nor a campaigning piece," she said. "It was a piece of fiction written about... moral issues like loyalty, guilt and not being able to kill... It was a very extreme situation which I don't think purported to be docudrama."
Accused airs on Mondays at 9pm on BBC One.