Hello,
Ashcroft invited me to these forums. I'm not a member of your group and saw this matter was discussed at different places over the forums, but since that's about some other subjects as well, I'll post my reply here. If this is for some reason not the right place, please move this to the appropriate location.
My name is Jordan Witherspoon and I am the commander of the JAG-department of the Alliance Navy. For I assume some or many amongst you don't approve on combat groups in SL, I suggest we will leave that fact as it is.
Within our group, we use a procedure for juridicial investigations in which chatlogs can be used. Every case starts with a report, filed by a member concerning a breach of conduct of any other member(s). For this to be possible, we have ofcourse agreed on rules, which are in our lawbook.
Any report can be accompanied by chatlogs. They hold no formal ground in the investigation, but are a good way for the JAG's investigating the matter to get an overview of what's going on. Also, any accussee can name potential witnesses to the alleged violation.
When we start an investigation, we will talk to both accused and accussee, and all witnesses if necessary. Before we start those talks, we always ask the ones we speak to if they mind the chat being 'recorded' in a chatlog.
All of these chats together form our investigation, which we close by writing a report to our Admirals to consider. In our report we attach the logs for reference. More important we summarize our findings and suggest a verdict.
The point with the chatlogs is, that we consider them just as memories from the ones questioned. Everyone can alter a notecard with a chatlog, so in that case we can't compare them to taps or audio recordings in any way, which can be considered quite trustworthy. Also, when we ask someone what he or she heard during a conversation, it doesn't really matter whether that recollection comes from a notecard of someone's memory; in a sense that's what notecards are for.
Basically, it all comes down to the credibility of the accussed, accussee and witnesses, as it always does in the courtrooms. We try to do our best in determining that, but it can't be flawless as can no law system.
For us, this system works pretty good. Noone ever disapproved of the chatlog being used and never has anyone questioned what's what being said in them afterwards.
For those interested; our procedures and lawbook are public and can be obtained in the AN-JAG Office at Enceladus (151,48,100). Although it's a quiet part of the sim, beware that it's damage land and someone could ask you what your business is. As long as you don't carry any weapons you should be safe though 
With kind regards,
Jordan Witherspoon
I'm happy to speak of these things again over there if those statements weren't clear.
It is good to get others involved in the debate about our legal system. It is also most interesting to know how others do it elsewhere; your experiences in the JAG are no doubt valuable, even though there is a great difference between civilian and militery law.