Since this was not based on any generally accepted science, how was this able to happen in Arizona state court?
Simple, the law allows someone who has specialized knowledge to testify from his or her own observation and experience in reaching conclusions even where no scientific principle is involved. If it helps a juror understand a fact in issue or the evidence, it is generally allowed to be heard. Being allowed to present this kind of expert applies to both plaintiff’s personal injury attorneys and defendant’s attorneys.
But what’s really involved here? When an expert is testifying from a generally accepted scientific principle, that principle has already been tested by those in the field. But when one is testifying from one’s own observations and experiments those may very well have been done in private.
The dog trainer was testifying to his own observations and experiments. The dog had been given the scent of an individual who may have had contact with a bicycle owner. It would have been important to the trainer to show the individual had contact with that bicycle owner. The dog trainer testified that after being given the scent, his dog identified that person’s scent on the owner’s bicycle. That bicycle had been in a lineup with 4 other bicycles. The dog had evidently picked it out. The trainer testified that the dog had communicated that the individual’s scent was on the particular bicycle.
While we all love dogs, some questions must be asked. For example, how old was the scent given to the dog, how do we know the dog was able to register the scent? What other scents may the dog have smelled before and after? How do we know the dog was actually linking a person’s scent to a bicycle? Can the dog do this every time? Is the dog trainer properly interpreting what the dog seems to be communicating? How does one test that? Does the trainer have motives, financial or otherwise, to testify as he did? Obviously more questions can be asked. It helps to have an experienced Arizona attorney.
Needless to say when an opposing expert testifies solely from his observations and experience, a thorough and effective cross-examination is a must.
Oh by the way, the Court later found the dog trainer to be a charlatan.
(This case was reported in State of Arizona v. Roscoe, 145 Ariz. 212  and 184 Ariz. 484 .)
If you or a loved one has been injured, contact the personal injury office of Jerrold Mayro today or phone (602) 604-8400 to schedule your personal consultation with Mr. Mayro.
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