Cruz, 44, of Oxford, is accused of kicking Zachary Bare, then 22, in the back of the head as he lay handcuffed and face down on the kitchen floor of the Exton house he shared with his mother. The impact drove Bare's teeth into his gums, leaving him bleeding from the mouth and nose.
Cruz has never denied that he inflicted those injuries. But he maintains that the alleged kick was actually a nudge to a shoulder, meant to restrain the man, who he said was screaming threats and struggling to stand.
"Make no mistake, Trooper Cruz's actions that night caused Zachary Bare's injuries," said Christian Hoey, the trooper's lawyer. "The question is whether it was a reasonable use of force."
Despite their disagreements, all parties agree that the Aug. 19, 2009, police raid that ended with Bare handcuffed and under Cruz's boot sole hardly went according to plan.
At the time, Cruz, the state police liaison to a Chester County drug task force, was assisting West Whiteland police in what was to be a surprise assault on a suspected meth lab in the Swedesford Road ranch house. But when officers arrived, the men inside spotted them, and one escaped.
Officer Jeffrey McCloskey told jurors Tuesday that he saw Bare running nearby and followed him to a house five doors down. He ordered Bare to lie on the kitchen floor, and Bare did, the West Whiteland officer said.
Another officer - Sgt. Matthew Herkner - testified that he handcuffed Bare and left him alone in the kitchen. That's where the agreement ends.
Glenn Cockerham, a third West Whiteland officer, filed a report later saying he witnessed Cruz yelling at Bare and then kicking him in the head. He is expected to testify this week.
And, said Hoey, there are enough other questions about that night to raise doubts in jurors' minds.
In their own reports, McCloskey and Herkner said they never saw Cockerham in the house at the time he claims he saw the alleged kick.
And though McCloskey testified that he zeroed in on Bare as a suspect based on description of the fleeing man as a white male without a shirt, Herkner, who called that report in, told jurors he had described a white male in a white T-shirt.
Hours after Bare was injured, West Whiteland investigators determined that he had not been at the suspected meth lab that night and released him without charges.
Bare's own story has changed, too. In early reports, he said Cruz kicked him in the face.
There is still another explanation of events that the jury is unlikely to hear.
Before he was federally indicted on civil rights charges last year, Cruz escaped charges when a grand jury in Chester County declined to indict him. Bare later sued the state police and won a $125,000 settlement from the department.
U.S. District Judge Mary A. McLaughlin has barred lawyers from mentioning either court proceeding in front of the current jury.
Still, Hoey maintains the twin threats of a criminal investigation and lawsuits gave West Whiteland police a motive to shift the blame for their bungled investigation to Cruz.
"This case boils down to credibility," the lawyer said in court Tuesday. "It all comes down to who the jury believes."
The trial is expected to resume Wednesday.