While cab driver Mitch doesn't go into details about his confrontation with Doherty, he admits he was disgusted to see the Babyshambles frontman backstage at Amy's gig at Brixton Academy earlier this month.
The Sun claimed Mitch smacked Doherty and hit him with a guitar at the Brixton concert.
Support: Amy Winehouse's father Mitch was unimpressed to see Doherty attend Blake's court hearing earlier this month
Speaking to Grazia magazine, Mitch said: "I do worry about people like Pete Doherty though. He's a scumbag.
"I flipped when I saw him sitting with Amy backstage at her Brixton gig. That night I went crazy.
"My wife thought I was going to have a heart attack, I was apoplectic..."
Mitch also hit back at criticisms that he should 'kidnap' Amy and force her into rehab.
He explained: "Believe me, my first instinct is to get hold of her, pick her up and take her back to my house and lock her away.
"But I've spoken to the finest drug counsellors in the world, and they've said that is exactly the wrong thing to do."
Mitch admitted he had been impressed by Amy's husband Blake Fielder-Civil's attempt to clean-up since he was imprisoned last month for perverting the course of justice.
Troubled pair: Amy and her husband Blake Fielder-Civil
Despite being against the whirlwind marriage earlier this year, Mitch says he respects Amy's choice of husband.
"I wasn't in favour of the marriage, but they are married and I will support them, and he's shown while he's been in prison a level of maturity that he didn't have before.
"I haven't seen him, but Amy says he's put on two stone and he's asking for her help to improve in a number of ways, and that's good to hear."
Meanwhile, Mitch concedes Amy is struggling being separated from her husband.
He said: "I know the real problem is she's depressed about Blake being in prison."
