MKOlsen101908_20_X17.jpgDespite being pretty avid Olsen twin fans, there are just some instances where it's hard for us to tell them apart.

Take these pix, for example, which sparked a pretty big debate in the office and several minutes of Googling before we eventually came to the conclusion that it's Mary-Kate and not Ashley.

Here's what misled us ...

Mary-Kate Olsen ashleyevidence.jpg

1) The lips. Ashley's upper lip is fuller than Mary-Kate's.

and

2) The thighs. Sorry, Ash, but again, yours are usually fuller than Mary-Kate's!

So does the evidence match up? NO! Despite all these signs pointing this being Ashley, the boho jewelry, the jacket, and the pin all equal MK!

Here she is again at LAX -- could you tell which Olsen?