Dame Barbara Mills, who was DPP at that time, gave the former Bishop of Lewes Peter Ball a caution, even though there was enough evidence to warrant putting him on trial.
She died in 2011.
Abuse victims have called the failure to prosecute Mr Ball until now an "establishment cover-up".
The Archbishop of Canterbury in 1993, Lord Carey, has strongly denied this, while the Crown Prosecution Service has said the way it handles sexual abuse cases is different today than how it dealt with them in 1993, and the decision it made then would not happen now.
A CPS spokesperson told Premier that regarding the current trial of Mr Ball: "We have worked extremely hard to overcome a number of complex legal challenges to gain the convictions we have today.
"We acknowledge the disappointment of those complainants whose allegations are not going to trial. This was a very difficult and finely balanced decision to which a great deal of thought was given.
"We believe this was the right decision for this case when taking into account all the circumstances. The decision to accept these pleas was explained openly and in detail to all the victims and the complainants in this case."
Regarding the 1993 decision to caution Mr Ball, the CPS told Premier: "In order to prosecute this offence today, we have had to conclude that the decision to caution was wrong - there was sufficient evidence and it was in the public interest to prosecute at the time.
"Furthermore, in order for a caution to be given, a suspect must first make full and frank admissions to the alleged offence. It is clear from our records that such admissions were not made in the appropriate way. Our approach to sexual abuse has changed fundamentally since 1993 and we are confident that such a decision would not be made by prosecutors today.
"Indeed, this prosecution is testament to our determination to robustly tackle sexual abuse, no matter how long ago it is alleged to have happened."
Mr Ball, 83, admitted eighteen counts of sexual abuse and one count of misconduct in a public office in court last week.
He's due to be sentenced in October.
