How does unboxing work in short-circuited boolean expressions?

How does unboxing work in short-circuited boolean expressions?

I recently tried to run the following two snippets of code and was
surprised at the output.
First:
// ...
System.out.println( (Boolean)null || true );
// ...
Second:
// ...
System.out.println( (Boolean)null || false );
// ...
The first example results in the following output:
true
The second example results in the following output:
Exception in thread "main" java.lang.NullPointerException
at com.blah.main(SanityCheck.java:26)
I would have thought both examples should result in a null pointer
exception, as any short-circuiting is applied left-to-right. The attempt
to unbox the boolean from the Boolean should have failed before the other
side of the logical or was given consideration.
Can anyone explain this inconsistent behaviour?