I hear now that Florida Governor Scott has appointed a commission to study the case. This has gotten ridiculous, this case needed police work, not a goverment commission that will probably take a year to write a report that leads to nothing. In Florida, shootings are pretty doggone common. This should have been handled long ago. The fact that no one official with the ability have Zimmerman arrested has done so is a shame and an embarrasment to fair minded people in Florida.
The initial police work was so bad that I think it is fair to ask if there was a conspiracy to suppress evidence. Zimmerman was was not drug tested although Martin was. His bloody shirt was not taken for evidence. There was no ballistics work done on his gun (good luck finding it now

.) No background check was done on Zimmerman although one was done on Martin. Apparently some witnesses were ignored, and at least one witness was told by the officer to change her statement to fit the scenario that officer felt should fit. Finally, the police did not check the cell phone records of Martin.
I think it is fair to say that there was no investigation at all.
The total indifference to the killing of Trayvon Martin is actually more upsetting to me than his killing. Individual racism or paranoia is terrible, but realistically, no one can ever control every biased or possibly demented person. The fact that the local police were so biased that they only sought information that would justify the shooting instead of trying to honestly assess the situation is something that no one deserves, at least no one with human decency.
If it is possible, I think the investigating officer should be indicted for some charge related to appears to me to be a conspiracy to suppress evidence and deny justice, and the administration of the Sanford PD needs to be fired.