The rope used as evidence in the courtroom is made of yellow hemp, but moments later, in the flashback scenes, it is made of white cotton fiber.
The TV crew car is followed and passed by a blue MGB. In the next shot, from behind, the car has disappeared.
One detective shows others how The Beatles' "White Album" has a song called "Helter Skelter". As he tells them this, he points to the Apple Records label on the record. The problem is, the label he's pointing to is the "sliced" label, which appeared on the even numbered sides of that (and any) Apple album. Since the song "Helter Skelter" appears on Side 3, the label should be of a green apple's body.
When the police take a man to identify the body of Sharon Tate, she is fully dressed in a blue house dress and shoes. Minutes later, two hippies are seen watching a news report about the Tate-LaBianca murders and the anchorman on the television states that Sharon Tate's body was found dressed only in a pair of flowered panties and bra. The news report wasn't real, it was reenacted for the movie. The statement by the news crew was accurate.
The time line for this movie is 1969-1971. During several scenes throughout the entire movie 1973 and newer Chevy Monte Carlo's, 1975 and newer Ford Granada's and 1974 and newer Ford Mustang II's can be seen in the background.
The Tate/LaBianca homicides took place in 1969. Yet some of the squad cars that are shown when the LAPD responds to the Tate house are 1971 Dodge Polaras. Besides being incorrect for the year of the murders, the LAPD patrol cars of the era were 1968 and 1969 Plymouth Belvederes.