Zimmerman "show trial"

It looks like Zimmerman's trial is just one step away from "show trial". Usually the term "show trial" was used to describe trials performed in Soviet Union, China, Eastern Block countries etc.

A judge said Thursday that jurors in the George Zimmerman case can consider the lesser charge of manslaughter, but she delayed ruling on whether they may also consider third-degree murder after defense attorneys called the proposal “outrageous.”

It seems that prosecutors think that they can pull new charges at any point of the trial depending how successful, or in this case unsuccessful, they are proving current charges. What is worrisome is that the judge allows such tricks.