It's the judge's responsibility to explain the legal basis to the jury in the form of jury instructions. These will usually be created in consultation with the lawyers for both sides.

Trial by jury is the reason why East Texas is the court of choice for patent claims. For some reason jury verdicts there seem to be biased towards the patent holder.

I should also note that being a juror in a federal case sucks. The first issue is that you're "on call" as a juror for 30 days instead of a day or two like most counties/municipalities. The second part is the cases are usually boring. People don't like to bring cases that they're likely to lose to a Federal court.

As 'tzs pointed out a few weeks ago, the East Texas issue is something that the America Invents Act (the recent patent reform bill) actually addresses:

http://news.ycombinator.com/item?id=3006925

> For some reason jury verdicts there seem to be biased towards the patent holder.

The jury is instructed to assume the patent is valid until they are convinced it is not.

If the patent holder's lawyer can confuse the jury, the patent will be upheld. It's pretty easy for a lawyer to do that.

> Trial by jury is the reason why East Texas is the court of choice for patent claims.

Not true. The local rules in the Eastern District are seen as favorable to patent plaintiffs. It's (basically) nothing to do with the jury pool out there.

Patent claims constructions are carefully written so as to present a decision tree to the court. The court translates the language into that decision tree worded for laypersons; expert witnesses for both sides make arguments at each node of the tree.

A good, simple starting point:

http://www.bpmlegal.com/howtopat5.html