Bon Cop, Bad Cop
How many times has this "dead-body-found-straddling-a-border-and-causes-cooperation/conflict-between-different-authorities" plot device been used? There are three I know of but my search keywords/phrases aren't finding any others. There's mention of an American version, but what's the title? Surely the Canadian one wasn't the first.
Bon Cop Bad Cop (2006) Canada
Two Canadian detectives, one from Ontario and the other from Quebec, must work together when a murdered victim is found on the Ontario Quebec border line.
http://www.imdb.com/title/tt0479647
The Bridge (2011) Sweden | Denmark | Germany
When a body is found on the bridge between Denmark and Sweden, right on the border, Danish inspector Martin Rohde and Swedish Saga Norén have to share jurisdiction and work together to find the killer.
http://www.imdb.com/title/tt1733785
The Tunnel (2013) UK
Set primarily in Folkestone and Calais where detectives Karl Roebuck and Elise Wassermann are called to investigate the death of a French politician. When a shocking discovery is made at the crime scene, the pair is forced into an uneasy partnership as they seek out a politically-motivated serial killer who draws them into his own personal agenda.
http://www.imdb.com/title/tt2711738