"The Spaniard" is named Efram Gonzales. Efram is not a Spanish (or Basque) name. The closest is Efraín (or Efraim), but this is such an uncommon first name in Spain that it would be pegged immediately as belonging to a Latin American immigrant. "Gonzales" is also a Latin American spelling: In Spain it would be "González".
(at around 4 mins) A Colombian police truck is shown which appears to be a Ford F-150 that is several generations more recent than those contemporary to the time period the series takes place in.
Murphy says that ETA murdered Spanish PM "Luis Blanco". His name was Luis Carrero Blanco: "Carrero" was not a middle name but the first of two last names. Thus he should be referred as "Luis Carrero" or "Carrero Blanco", but never "Luis Blanco".
Murphy claims that ETA murdered Carrero Blanco when he was "returning home from Christmas Mass". He was murdered on December 20, while going from morning mass to work.
When Steve Murphy is holding the Spaniard's file (Carlos Aguilar), it says that his height is 6'4, in fact Carlos Aguilar is 6 feet.