DWI cases at risk as credibility of lab expert questioned

DALLAS (AP) — Thousands of DWI convictions in North Texas could be jeopardized after the testimony of a state forensic scientist recently came under scrutiny.
Christopher Youngkin was involved in a 2013 lab error in which two blood samples from separate cases were mixed up. Youngkin erroneously reported to police that a woman had a blood-alcohol level above the legal limit when in fact she hadn’t been drinking.
Defense attorneys now are questioning whether Youngkin in recent cases ha