Zimmerman, the neighborhood watch volunteer charged with second-degree murder in Martin's February shooting death, had harshly criticized the Sanford Police Department at a January 2011 public meeting at City Hall, an audio recording obtained by CNN revealed.
"I also have had the opportunity to take ride-alongs with the city of Sanford Police Department and what I saw was disgusting," Zimmerman said at the meeting. "The officer showed me his favorite hiding spots for taking naps. ... He took two lunch breaks and attended a going-away party for one of his fellow officers."
Zimmerman said at the meeting "the law is written in black and white. It should not and cannot be enforced in the gray for those that are in the thin blue line."
Sanford Police Capt. Robert O'Connor told CNN the department has no details about Zimmerman riding with police, with whom he rode or "if in fact he ever did ride with SPD."
By September 2011, Zimmerman expressed a much more positive view of the police, saying he had a "completely new perspective" after working with the department's volunteer coordinator as part of neighborhood watch efforts, an e-mail to the then-police chief said.
Zimmerman praised the volunteer coordinator and called her "a testament to the highest level of professionalism of (the chief's) administration."
"I have high hopes for, and restored faith in your administration and the Sanford Police Department in its entirety," Zimmerman wrote.
Beginning in August 2011, court documents show, Zimmerman exchanged e-mails with the department at least three times. He asked the police department to host a neighborhood watch presentation, which it did Sept. 22.
Martin's shooting on Feb. 26 sparked protests and debates about race relations and gun control. Zimmerman is white and the 17-year-old Martin was black.
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