To do a Mehew means
to humiliate one's self in front of a vast array of people. The phrase
a young man performed an act of defecation upon a street in London, Islington after a pop concert.This uncontrolled
defecation lead to widespread humiliation over hundreds of people as it was too funny
not to tell anyone. Seconds before
this act he uttered the immortal words: 'I Really Need A Poo'.