According to the affidavit, Gilbreath has 36 years of LE experience, including 24 years of homicide investigations.
I highly doubt that he would committ perjury, even potentially, which is defined as "wilfully gives false evidence" in any court proceeding about one of his cases.
The affidavit also states:
"Your Affiants, along with other law enforcement officials have taken sworn
statements from witnesses, spoken with law enforcement officers who have provided sworn testimony in reports, reviewed other reports, recorded statements, records, recorded calls to police, photographs, videos, and other documents in detailing the following....."
IOW, there are many ways that the lead investigator (supervisor) in a case receives information and testimony without having to personally take a statement or even read the statement himself.
http://www.centurylink.net/news/read.php?rip_id=<[email protected]>&ps=1018&page=2