Los Angeles, Dec 30 (DPA) The teenage father of Sarah Palin's grandchild has won a crucial court victory in a bitter child custody battle, portraying the one-time vice presidential hopeful as 'vindictive' and 'malicious', the Anchorage Daily News reported Tuesday.

The report said that a judge in the case had sided with Levi Johnston, 19, to have the hearings open to the public despite the request of Bristol Palin, also 19, to keep the deliberations behind closed doors.

Palin is the daughter of Sarah Palin, the failed vice presidential candidate in Republican John McCain's bid for the 2008 presidency.

Palin asked for sole custody of one-year-old Tripp in November and also requested a gag order so none of the parties involved could talk about the case.

'This is a routine matter, but the parties' respective celebrity status mandates the protection of the baby ... whose privacy interests should be protected until and unless one day the child decides otherwise,' her lawyer wrote.

But in an affidavit, Johnston said that a public hearing was a better strategy to keep Sarah Palin's 'sheer malice' in check.

'I know that public scrutiny will simplify this matter and act as a check against anyone's need to be overly vindictive, aggressive or malicious, not that Bristol would ever be that way, nor that I would. But her mother is powerful, politically ambitious and has a reputation for being extremely vindictive,' Johnston said in his affidavit. 'So, I think a public case might go a long way in reducing Sarah Palin's instinct to attack.'

Palin denied her mother was involved but Alaska Superior Court Judge Kari Kristiansen ruled that she hadn't provided any evidence that Tripp would be harmed by the anticipated publicity. She ordered all the sealed records opened.