Phillips to Cops: Thanks for Arresting Me!

It's one of the most remarkable turnarounds ever -- Mackenzie Phillips just had the slate wiped clean in her drug case -- and in court just moments ago, she thanked the police for putting her behind bars in the first place.

Phillips -- who was ordered to complete a drug diversion program back in 2008 -- had all charges against her dismissed.

She calls her recovery "the most rewarding time in my life ... It really just changed my life."

On her way out of court, Mackenzie had a few words of wisdom for Lindsay Lohan: "I hope she finds the strength within herself to get some help ... I had to go until I had to walk out with handcuffs on and I don't want to see that happen to her."

Mackenzie looks and sounds amazing.  Congrats!