Lead detective recounts how evidence in Katrina Smith murder case led to her husband, Todd Smith

Lead detective recounts how evidence in Katrina Smith murder case led to her husband, Todd Smith

ROCKFORD, Ill. (WTVO) — The murder of Katrina Smith in Rockford in 2012, by her husband, Todd Smith, is the subject of a new 20/20 special, "Deadly Vows," which airs Friday, October 20th, on ABC and will stream on Hulu. John Berg, now retired from Winnebago County Sheriff's Department, was the lead detective on the case. "It was such a complex case and it had so many twists and turns," he said. "This was a very extreme case. It lasted weeks and …