Lindsay Lohan: 'I Don't Do Drugs'

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TMZ has obtained a statement Lindsay wrote in connection with her 2007 arrest for driving under the influence of drugs and alcohol, following a wild chase on Pacific Coast Highway.

As we just reported, according to the police report, Lindsay's urine showed the presence of cocaine.

And cops say they found a small amount of cocaine in Lindsay's pants pocket, but Lindsay had an explanation for the police: "I am wearing a pair of borrowed jeans from a friend/assistant ... She wore a pair of my jeans ..."

Lindsay also said, "I am sober. Promises in Malibu, CA, I left 2 wks ago or so & completed my stay & am & will continue to be drug free."

And Lindsay goes on: "[the assistant] and her boyfriend currently use & may have set me up."