So you're saying someone robbed you but credited you change so as to exactly pay himself 1 BTC? Go through your financial history, figure out which service you paid 1 BTC to and take it with them...
that's the thing i could not have sent even if i had tried. I was unable to send bitcoins from my MAC wallet long before that transaction was made(Jun7). I even made a post about it.
https://bitcointalk.org/index.php?topic=1932422