Someone said :
You Write a letter which you say and admit is an error of judgement but you don't withdraw it and it's read in court so you could have taken it back ?
Why didn't you?
You had time.
Is it a case of say one thing and do another?
A character reference for court purpose would more than likely be in the form of some sworn affidavit.
It reflect what you swore to at the time: it cannot just be withdrawn, if it has already been filed with the case.
All you could do is lodge another affidavit, but you cannot suggest the previous reference was a lie or a mistake, as it could constitute perjury.
The really annoying thing is not that he wrote it, and that after the fact (too late to "retract" it) he regrette it. The unacceptable thing is that such statements are admitted in the first place! That being a "GAA man", a good neighbor and a cool friend, can be seen as a mitigating factor in sexual abuse!