I (non-native English speaker) have sometimes been confused about when to use past simple and when to use past perfect.
President Donald Trump has vetoed a measure from Congress that revoked his declaration of a national emergency at the US-Mexico border.
Lawmakers, including 12 Republicans, had passed the rejection resolution on Thursday in a surprising rebuke of Mr Trump’s signature issue.
Why does this news article use 'had passed(past perfect)' instead of 'passed(past simple)'?
If I use 'passed', what is the difference between two sentences? (expecially relating to 'on Thursday')
Lawmakers passed the rejection resolution on Thursday.
Lawmakers had passed the rejection resolution on Thursday.