Cop Thought Lindsay's Coke was a Breath Mint

Linday Lohan's coke angels must have been watching over her the night she got arrested for DUI in 2007 because the officer who found her coke stash didn't recognize what it was and threw it in the trash.

Now we know why Lindsay Lohan's 2007 DUI case may have plea bargained so quickly -- the cop who took custody of the cocaine mistook it for a breath mint and threw it in the trash.

Pretty incredible, but according to the Santa Monica Police report -- obtained by TMZ -- the officer "discovered a folded Clinique sun care card with an unknown substance caked on to the surface of the card in Lohan's right rear pocket."

The report goes on: "Some of the white substance fell to the floor. I used my foot to see what had fell but thought nothing of it. I did not recognize the substance attached to the card and initially thought the substance was a wet crushed breath mint."

And now it gets good: "I put the card into the jail trash can next to the booking windows. I was looking at the floor and began to recognize the substance as resembling powder cocaine. I then recovered the card from the trash."

The cop says the coke was in the trash for about 2 minutes. He put the card in an evidence envelope, then scooped up the coke that had fallen to the floor and placed it in a separate evidence envelope.

In short -- EVIDENCE CONTAMINATION!!!

Lindsay ended up with a sweet deal and spent 84 minutes in jail ... for a drunken, cocaine-fueled chase on Pacific Coast Highway. Nice deal if you can get it.

Jacked from TMZ