My uncle was a prosecutor, and once made the point that (among other things) police officers are trained observers. So much of criminal enforcement seems to depend on cops showing up, talking to people, and writing stuff down. (That goes double when the witnesses are somewhat dubious themselves.) I just finished jury service in Superior Court, and the ability of the jury to convict a bad guy absolutely hinged on the testimony given by officers, and testimony of others recorded by officers.
Care to comment?