From this extensive presentation of evidence and argument, the following conclusions
ineluctably emerge. In their zeal to bring charges against the defendants in this case, the prosecutors and investigators aggressively sought out statements the defendants had been compelled to make to government investigators in the immediate aftermath of the shooting and in the subsequent investigation. In so doing, the government’s trial team repeatedly disregarded the warnings of experienced, senior prosecutors, assigned to the case specifically to advise the trial team on Garrity and Kastigar issues, that this course of action threatened the viability of the prosecution. The government used the defendants’ compelled statements to guide its charging decisions, to formulate its theory of the case, to develop investigatory leads and, ultimately, to obtain the indictment in this case. The government’s key witnesses immersed themselves in the defendants’ compelled statements, and the evidence adduced at the Kastigar hearing plainly demonstrated that these compelled statements shaped portions of the witnesses’ testimony to the indicting grand jury.2 The explanations offered by the prosecutors and investigators in an attempt to justify their actions and persuade the court that they did not use the defendants’ compelled testimony were all too often contradictory, unbelievable and lacking in credibility.
When you read the full file, it's hard to believe that the amount of disregard for the actual process that was put into place to prevent the court case from being "tainted" could have not been purposeful. Another example:
In direct contravention of Hulser’s unequivocal warnings, in January and February 2008, the government’s trial team interviewed all of the DSS agents who had conducted the September 16, 2007 interviews and specifically inquired about the details of the defendants’ statements during those interviews.
The opinion is 90 pages long, but I really recommend reading it if you are interested in what happened. I also recommend reading this for those of you interested in what the current status of the civil suit that was filed against Blackwater.