No DP in Michigan, but I'm not sure about Ohio. I've been thinking about this since the presser at 11:00. If it's believed that the boys are dead, were they killed in their Michigan home, or did Dad do the deed across the state line? If the timeline is correct, and the dad left the house between 4:00 and 7:00 in the morning on Friday, were the boys already gone, or were they alive in the van for a while before they met their demise and possibly in Ohio?
Buckeyes, please inform about DP in your state. Thanks.
ETA: Did a cursory search and found the answer: Yes, Ohio has DP.