George Michael will not face any charges after he fell out of his car on the motorway.
The former Wham! star was airlifted to hospital with a head injury after falling from his vehicle on to the road last month.
An eyewitness who was behind the 49-year-old singer's vehicle said she saw him lying on the road surface smeared with blood.
The singer gave traffic police a statement and officers have now closed the case.
A spokeswoman for Hertfordshire police said: "Following a thorough investigation into a collision on the northbound carriageway of the M1 on May 16, police are no longer investigating this incident and no further action will be taken in relation to this incident."
George was treated at the scene and then taken to hospital by air ambulance following the accident, the latest car drama for the troubled singer.
The singer was close to death only 18 months ago after being struck down with pneumonia in Vienna, but he fought back to perform again.
In 2010, he received an eight-week prison sentence following an incident the previous July in which he crashed his Range Rover into a shop in north London.
He was also given a five-year driving ban after he pleaded guilty to driving under the influence of drugs and possessing cannabis.
And he had earlier been banned from driving for two years and sentenced to 100 hours of community service in 2006 when he was convicted of driving while unfit through drugs after he was found collapsed in his Mercedes.