The inimitable Grits for Breakfast took on the mistrial of Robert Yetman, in a particularly interesting post. I highly suggest taking a look at it. In his post, Grits points out:
"Criminal trials are always high-stakes endeavors for the concerned parties, but where the charges are politically sensitive, or the defendant unusually powerful or well-connected (i.e., the antithesis of the ordinary criminal defendant), the imperative of prosecutorial victory is heightened, the sense of prosecutorial isolation and embattledness is exacerbated, and the already-fraught counterweight of a duty to "do justice" is put under more extreme pressure. "
I think this adequately describes the circumstances surrounding Coy's trial; Yetman was accused of a similar crime, and it's encouraging to see that Harris County is looking a little closer at cases of this nature.