Jill is wearing slacks and flat shoes when she receives the email and phone call from the reporter being held by the murderer. She then leaves to meet her in the parking garage where she is now wearing a skirt and high heels.
The unsub's torture notes shows an incorrect electrical calculation, E=(20mA)(1M ohm) = 20,000 kV. The correct result should be 20,000 V.
The television is broadcasting the news on channel 7. In Philadelphia, the news would be on channel 3 (KYW-Eyewitness News, national affiliate of CBS) or channel 6 (WPVI-Action News, national affiliate of ABC).
When the murderer picks up his victim and puts her in the back of his van, the body is obviously a mannequin, not a human being.
When the victim's car is hit from behind by the killer's van the cameraman's hand and camera are visible when the victim looks behind her.
People from Philadephia don't say I-76, because it is both the PA Turnpike and the Schukyll Expressway. A local would specify.
The voiceover at the end has SSA Rossi quote Lucille Maud Montgomery when in fact the name of the author is Lucy Maud Montgomery.
When Jill is comparing the handwriting in the unsub's journal to the letter emailed to her by Kat, "definitely" is misspelled as "definately" in the journal.