What?  Dog should not be used?  Your reasoning doesn't make any sense.  The K-9 is a very effective tool to expedite the capture of the suspect quickly to reduce chances of them causing further harm to other people or property.  Why do you feel the LEO should be on equal terms with the criminal.  They are not there to provide a fair fight for the criminal, they are there to stop them as quickly and effectively as possible using whatever tools are available to them.  Premeditated attack?  It just happened that one of the responding officers was a K-9 unit.  Again, they used the tools available to them that were appropriate for the situation.