The cartel assassin uses a bolt action sniper rifle, when he is shooting at Lucia he fires it rapidly as if it is a semi automatic without cycling the bolt.
When the Team is investigating the Diamond Heist scene during the opening credits the CSI is taking photos in the News Report but he is triggering the flash manually and his finger is not on the shutter button.
At the 3:17 mark, while credits are still running, his finger is on the shutter, but he is still triggering the flash manually.