This isn't necessarily the evidence they are using. Instead, it is the stuff that the defense asked for. (Think: "you're accusing my client of robbing the bank. For our defense, we need to see every picture you've ever taken or seen of the bank in question. And the same for the potential getaway vehicle, be it SUV, sedan, scooter or sneaker.") But if the defense asks for something and prosecutors don't produce it, the prosecuting side can't later bring it in. So prosecutors are overloading it, to prevent them from saying "we also need X," and to get anything that might come up on the record.
This isn't necessarily the evidence they are using. Instead, it is the stuff that the defense asked for. (Think: "you're accusing my client of robbing the bank. For our defense, we need to see every picture you've ever taken or seen of the bank in question. And the same for the potential getaway vehicle, be it SUV, sedan, scooter or sneaker.") But if the defense asks for something and prosecutors don't produce it, the prosecuting side can't later bring it in. So prosecutors are overloading it, to prevent them from saying "we also need X," and to get anything that might come up on the record.