The jury also convicted Seacat of aggravated arson and two counts of endangering a child for setting the couple's home on fire to try to cover up the murder, HLN reported Tuesday.
The couple's 2- and 4-year-old sons were in the house at the time of the arson.
Judge Larry Solomon scheduled sentencing for Aug. 5. Seacat will either face life in prison without parole or life in prison with the possibility of parole after 50 years, HLN reported.
Prosecutor Amy Hanley said Seacat shot his wife and burned down the house to make it look like she killed herself because he was angry she had filed for divorce.
Hanley said the fact Seacat was a police officer meant he knew how to manipulate evidence.
Defense attorney Roger Falk said Vashti Seacat killed herself because she was depressed due to a side effect of medication she was taking.
Falk also argued investigators made too many mistakes in the case, including the coroner's inability to determine Vashti's cause of death.
"Someone with over 3,000 autopsies under their belt sat here and told you, based upon all of their experience and training, 'I can't tell if this is suicide or homicide,'" Falk said.
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