Continuity mistake: In the closing scene, Megan is sitting at her desk and Peter walks in. Megan's LCD is sitting in front of her and slightly to her left. In multiple shots it can be seen very close to a picture frame on her desk right in front of her. Peter gives her a memory card and she puts it in a reader, then views the video. Her eyes are basically straight ahead while she watches the video. At the close of the scene, the camera zooms back from Megan and the LCD has moved to her extreme left near the edge of the desk. Note the distance between the LCD and picture frame from earlier. (00:40:00 - 00:43:10)
Factual error: The opening scene is supposed to be a deer hunt, but if the police and coroner are from Philadelphia, there are many errors. Clothing is not right for November or early Dec., PA gun season, and there is not enough orange to meet game regulations. Philadelphia County is "archery only" and all surrounding counties are "shotgun only", so there would be no rifle or bullet in a murder staged as an accident. The key evidence is pollen from a leaf from a Southern Red Oak, not usually found in PA, but no leaves are on deciduous trees in PA in deer season, let alone leaves with pollen.
Continuity mistake: Peter says he only found out he was adopted only because his father gave him an envelope before he died. However, in the first season, Peter said that as a kid he was bounced around foster care until he was adopted by a good family with three sisters. (00:18:15)
Factual error: Hunt and the CDC Doc Stafford discuss an experimental vaccine for an outbreak to give to already infected people. That's not how vaccines work. You have to have it before you get sick to prevent you from having it or having a reduced response to the virus. What they're talking about is a cure/antiviral drug, not a vaccine.
