For those more familiar with legal proceedings : Was the defense not able to submit the IM context themselves? The conclusion seems to be that it would basical

For those more familiar with legal proceedings : Was the defense not able to submit the IM context themselves? The conclusion seems to be that it would basically exonerate him, so why could they not disclose it? The article goes so far as to mention the context "hasn't surfaced". Why on earth not? Is this because Facebook refuses to release the IM history?