Mr Finucane's son, Michael, told reporters that while there was new material in the report regarding the extent of the threats, "it doesn't really take you much further in terms of the culture".
Previous reports had made clear that it was the "overwhelming priority" of agencies to protect intelligence sources even if there was a "human cost", he said.
"David Cameron referred repeatedly in the House to what went wrong here," he added.But he told the press conference "nothing went wrong here".
"This is exactly what it was designed to do: to improve and focus the targeting abilities of loyalist paramilitaries over many years.
"A thorn in the side of the authorities could be removed, killed, in circumstances where the state could deny any responsibility."
There were probably "hundreds of others" killed in similar circumstances, he added.