How Difficult Was It Back in the Nineties to Combat the Non ID Defence?

It was really down to a misidentification defence, that the person that has been charged with this homicide wasn't the shooter, or wasn't even there. The alibi was that who was spending new year's eas with his girl friend. And she gave a very detailed account of everything they did and when they ended up back at her apartments on New Year's Eve. They could have gone self defence, but again, they had multiple people out there that saw what transpired. So again, if they were going to choose something, this alibi, this mis idea, really was the way to go. But without that, how difficult was it back in the nineties to prove a non