Zimmerman's case...

[Fudd]

Seems the judge is allowing all of GZ history, even from years ago, but not allowing anything from TM history such as his school records, or more precise, his expulsion from school, drug related activities, school bus driver beating...
In other words, the fact he was going (or already gone) down the wrong path and becoming another burden on society because his parents failed miserably in raising him properly.

That's because GZ is on trial, not Trayvon.

It doesn't seem fair, being that it's Zimmerman's future is on the line, but that's the rule.

However, the prosecution has to be damn careful not to say anything painting Martin as a wholesome, innocent, upstanding young man of good character.  They will be opening the door for a defense rebuttal.  I'm sure Zimmerman's attorneys have a whole notebook full of information that the jury might find 'interesting.'