I am very sorry for your loss.
I researched your issue earlier and Dimitry asked me to go ahead and post your answer to prevent delay.
Your attorneys are correct. This is an issue that involves a very simple rule of evidence. California Evidence Code 350 and 352 exclude evidence that is not relevant to the issue presented to the jury. (http://www.leginfo.ca.gov/cgi-bin/displaycode?section=evid&group=00001-01000&file=350-356) Admitting liability is actually a very common defense strategy where liability is clear or the circumstances of the incident may inflame a jury to render an emotionally inflated verdict.
When a defendant admits liability and limits the jury question to damages he/she renders the circumstances of the accident irrelevant. Take a look at Sumrall v. Butler, 102 Cal. App. 2d 515 (http://login.findlaw.com/scripts/callaw?dest=ca/calapp2d/102/515.html).
There is one thing that could make the circumstances of the incident relevant. Punitive damages are severely limited in wrongful death actions (they actually must be joined in a separate survival action), however if a plaintiff were to seek punitive damages and survive a motion for summary judgment then it would be possible to create relevant issues that involve the circumstances of the offense. As I have said, punitive damages in wrongful death cases are VERY rare and difficult to maintain, however it is a conversation you should have with your attorney.
This is obviously a very difficult issue.
Please reply if I can help further.
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