The police cars in the game have normal license plates such as the way they say California at the top then under it they have random numbers and letters. However, a real police car would say CA Exempt and under it would be all numbers, no letters.
The North Korean general refers to his country as "North Korea". North Koreans (at least those loyal to the regime) never refer to their country as North Korea as they view the term as offensive, preferring instead to call it the "Democratic People's Republic of Korea" or "DPRK".
The LAPD cars' lightbars are blue on driver's side when they should be on the passenger's side.
The LAPD cars have no emblems or writing on their doors, which they should have.
There is a mission in which you must break into a nightclub, which shows the Hollywood sign as being behind it. When you look later, there is no sign and the club is on the wrong side of the road, with the back facing the city and no cliff behind it.