In day eight of testimony, the lead Plano police detective responsible for investigating Loper's death took the stand.
He stated his department never went after Jayson Hayes, Loper's on-again, off-again boyfriend at the time of her death, nor Craig Loper, Susan's ex-husband.
Defense attorneys argue authorities should have ordered DNA testing on more evidence at the crime scenes, especially because there was unidentified male DNA on Loper's clothing at the time of her death.
The defense called a private investigator to the stand.
That investigator drove a route defense attorneys say Hayes could have taken to commit the crime before arriving at work.
The investigator stated that had Hayes not taken Dallas toll roads where his toll tag would have registered, he could have committed the murder before arriving at work the morning Loper was killed.
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