Factual error: When Riggs and Murtaugh go to investigate the scene where the body of Ramon Alvarez is discovered Scorsese states that Alvarez's dog tags say "SEAL" on them. His dog tags would not say that he is a SEAL on them. The information listed on dog tags is as follows: Name, Social Security Number, Blood Type, Service Branch, and Religious Preference. There is no way to tell what a given service member's MOS (job) from his or her dog tags. (00:14:00)
Surf N Turf - S1-E2
Other mistake: When Riggs calls the arms dealer's phone (agent Hirsch), Hirsch doesn't answer the phone, silencing the call and putting the phone in his pocket, but Riggs leaps to action and says "it was Hirsch's voice on the phone!" Realizing that the arms dealer and Hirsch are the same person but no-one answered the phone. (00:32:00)
Suggested correction: When Hirsch ignored the call, it would have gone to his voicemail. That was the voice Riggs would have heard on the phone.