The father of Amy Winehouse has now threatened legal action against the makers of a new documentary about the late singer's life.

After first distancing himself from the project with a press release, Mitch Winehouse has gone further by suggesting the filmmakers are guilty of libel and slander.

At issue is the film's depiction of the 65-year-old professional jazz singer's alleged inadequate efforts to seek treatment for his daughter's ongoing addiction issues.

Winehouse Sr. is also incensed that the filmmakers included an interview with his daughter's ex-husband, Blake Fielder-Civil, laying the blame for Amy's out-of-control drug use firmly at her father's feet.

In an interview with Britain's The Sun, Mr. Winehouse claims:

Blake is saying in the film that the reason Amy was like that was because of me — not because he gave her crack and heroin and because he completely manipulated and coerced her into Class A drugs. If the real truth came out about Blake, he wouldn't be able to walk down the street, so how they can allow him to make that claim about me is so hurtful and beyond belief.

However, the filmmakers have defended the documentary, saying:

When we were approached to make the film, we came on board with the full backing of the Winehouse family and we approached the project with total objectivity. During the production process, we conducted in the region of 100 interviews with people that knew Amy Winehouse; friends, family, former-partners and members of the music industry that worked with her. The story that the film tells is a reflection of our findings from these interviews.

Blake Fielder-Civil has claimed in past interviews that Amy's drug and alcohol problems long predated their relationship. Nonetheless, during their time together, he was seen by the public as the villain who seduced and coerced the emotionally fragile singer-songwriter into using opiates.

Meanwhile, Mitch Winehouse has tried to position himself as Amy's one champion and the protector of her legacy. As Popdust previously reported, he has written two books about his daughter's short life and heads a charitable foundation in her name.

As we await the release of the documentary, it's worth remembering that addiction is a complex issue that can't be blamed on any one person or event. No doubt all of us would have done anything to rescue Amy Winehouse if that were possible.

Amy: The Girl Behind The Name is due to premiere at the Cannes Film Festival in May.