When Susan/Sadie is dumpster diving for French fries, the straps on her dress change position repeatedly between shots (tied/untied, on the shoulder/off the shoulder).
During Susan Atkin's testimony, Bugliosi approaches her with two photographs in his hand and asks her if she can identify the car belonging to victim Steve Parent. As he approaches, the photograph visible in his hand is clearly a black and white photo of a car parked in front of a building. However, when he hands the photo to her, the insert shot is a color photo of a car parked in a wooded drive. The other photo is that of Parent slumped dead behind the wheel and there were no other photos.
As Linda is going through Rosemary Labianca's wallet, VISA and Master Cards can be seen. In 1969 Visa was called Bank AmeriCard and Master Card was called Master Charge.
The story takes place in 1969 but the phone Sharon Tate is talking on has an RJ10 connector which was not introduced till the late 1970s.
When Squeaky takes Linda's wallet, she opens to a photo driver's license. Driver's licenses did not include photos until the late 1970s.
The opening credits montage of iconic '60s imagery includes an adult cinema marquee showing the film Cry for Cindy (1976) which wasn't released until 1976.
Both actors portraying Leno Labianca and Vincent Bugliosi respectively,speak with thick, New York/New Jersey accents. Leno Labianca was a born and bred Californian who never used this speech pattern, and Vincent Bugliosi was born in Minnesota but spent most of his life in California.