There was a US supermarket that threatened a customer who was suing them after he slipped in their store - they said they would present the history of his liquor purchases to suggest to the court he was alcoholic
That is exactly the kind of insinuation that evidence rules are designed to protect against (in my layman's understanding of the law). From Federal Rules of Evidence, rule 404 (http://www.law.cornell.edu/rules/fre/rule_404)
"Evidence of a person’s character or character trait is not admissible to prove that on a particular occasion the person acted in accordance with the character or trait."
I can't comment on the legal accuracy of that interpretation of the law, but as someone who has performed jury duty on a number of occasions I can say that whatever the letter of the law, character assassination, in lieu of objective evidence, is common and very routine.
Your jury duty experience was different than mine then. I sat on a criminal trial where we were told almost nothing about the numerous past convictions of the defendant, the fact that he beat his girlfriend, or the fact that the trial's key witness had been beaten shortly before the trial began in an apparent effort to prevent her testimony. I learned about all these things only when the trial was over. The judge even threw out a recorded phone call that the defendant placed from prison because it repeated some boilerplate disclaimers about the call being from a prison inmate.
My jury experience led me to believe that evidence rules are very stringently applied.
It seems to me you are comparing apples to oranges: Criminal charges are not the same as a civil suit (i.e. "being sued"). It is why I opted to not put in my two cents: I think my experience probably doesn't apply.
They're not the same, but it appears that evidence rules apply to both. In particular, the Federal Rules of Evidence that I cited applies to both, according to Wikipedia: http://en.wikipedia.org/wiki/Federal_Rules_of_Evidence
My experience with this: I worked at an insurance company for five years. A lot of what we did was driven by questions of what would hold up in a court of law if we got sued. Generally speaking, proving someone was an alcoholic had no bearing on the decision (there were exceptions: some policies had odd language driving those exceptions).
Vons threatened to introduce the issue at trial. They were not allowed to introduce the evidence at trial, and they did not.
Ultimately, the shopper failed to prove his case. He claimed Vons was negligent for not cleaning up spilled yogurt, but during the trial somehow failed to prove (1) that there was some spilled substance which would have caused him to slip and (2) that his knee injury was caused by the slip and not by subsequent activities after he left the store.
Seems like a stupid threat anyway; the fact that you have a history of alcohol abuse does not mean that you were impaired when the incident took place, and it doesn't mean that the store was maintaining a safe environment for its invitees.
It doesn't matter. All you have to do is suggest the plaintiff is an alcoholic, and let the jury infer the rest. Ad-hominen attacks are par for the course in trials, because they are incredibly effective.
Let me repeat myself: Vons was not allowed to bring up the information about the plaintiff's alleged alcoholism. The jury would not have been allowed to hear this information in any court unless Vons could have shown (to the judge, before trial) that alcohol played a direct and immediate role in causing the plaintiff's injury.
But if the plaintiff was an upstanding member of the community, then the threat to publish alcohol sales - even if he wasn't an alcoholic and they weren't unreasonable - might be enough to convince him to drop the suit.
