It's been upheld because he didn't allow any evidence that undermined Michael's case, and that is all they are looking at.
Get yourself informed. Here's a start:
Here's a summary:
http://www.nationalreview.com/comment/comment-smith090503.asp
A few other links of interest
The Melton audit of Judge Greer (corruption in the elderly care system)
http://straightupwsherri.blogspot.com/2005/03/whats-really-driving-death-train-for.html
stories about corrupt law enforcement in cahoots with this guy
http://www.theempirejournal.com/0319051_former_sheriff_rice_unea.htm
http://www.theempirejournal.com/0320053_lee_county_retired_sheri.htm
All legal, if unjust, under the system of law in Florida....