The “Rehab” singer, 24, voluntarily met with police Friday for questioning after tabloid reports that she allegedly head-butted a man who tried to hail her a cab outside a bar in London on Wednesday.
Winehouse was cautioned by police about the incident, which will remain on her record and could be held against her if she gets in more legal trouble down the road, according to the Associated Press.
The Grammy Award winner, who went to rehab in January, “looked a mess” on her way to the station Friday, an eyewitness told Usmagazine.com.
Winehouse’s husband, Blake Fielder-Civil, has been in jail since November on charges of assault and witness-tampering.
A judge ruled on Friday he will remain in jail until at least June 9.
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