Array is splicing for no reason?

programming flash
1 

var remoteListArray:Array = new Array();
var listArray:Array = new Array('a0','b1','c2','d3','e4')
var listPosition = 3;
function makeRemoteListArray() {
     remoteListArray = listArray;
     remoteListArray.splice(listPosition+1);
     trace(remoteListArray+" ORIG: "+listArray);
}
makeRemoteListArray();
stop();
// Output
// a0,b1,c2,d3 ORIG: a0,b1,c2,d3
// Should be
// a0,b1,c2,d3 ORIG: a0,b1,c2,d3,e4

Any way to stop it from splicing the original? or do I need to use slice or what?