Defense arguments in the trial of Carlos Miguel Zacarias, who was acquitted of first-degree murder on Tuesday, focussed heavily on the testimony of eyewitnesses.

Defense attorneys brought in a professor emeritus in psychology from the University of Texas, El Paso who testified about some of the issues with eyewitness accounts of crimes and photo lineups that police often use.

Roy S. Malpass, who has written numerous academic articles on issues of areas of face recognition and eyewitness identification, testified that photo lineups can create a high-pressure situation for potential eyewitnesses who might feel obligated to identify someone as the culprit.

Malpass also said in-court identifications, commonly used during witness testimony at trial, creates a similar high-pressure situation.

Zacarias was accused of the shooting death of Grayeagle Ortiz, who was killed in a drug deal.

Read about the trial here and here.

Read about Malpass' research at the Eyewitness Identification Research Laboratory here.

Contact reporter Patrick McNamara at 573-4241 or On Twitter @pm929.