Nigella Lawson would lock herself in a bunker for hours says former aide Nigella Lawson aides Francesca and Elisabetta Grillo are found not guilty of fraud. A SECRET room was built in Nigella Lawson's $27 million Chelsea mansion, it was claimed yesterday. She spent hours hidden in the bunker, which she nicknamed 'The Cell', according to her former housekeeper Francesca Grillo. The Italian aide said: 'She'd lock the door and tell nobody to bother her. It was like her own bunker. Occasionally she'd text one of us to bring her some tea but that was it.' Miss Grillo said Miss Lawson could become very demanding when upset: 'She was like "Francesca, where is my water? Why didn't you order potatoes? '"Why aren't my shoes stretched? Why aren't the children awake? Why is the wine running low? It felt like we couldn't win with her.' As her two former housekeepers were acquitted of a $1.2 million card fraud, Miss Lawson said she had been 'vilified' by the court process despite having done all she could to alert the Crown Prosecution Service to a 'sustained background campaign deliberately designed to destroy my reputation'. Italian sisters Elisabetta (L) and Francesca Grillo, former assistants of British television chef Nigella Lawson and her former husband Charles Saatchi. Nigella Lawson was effectively put on trial without a lawyer, her furious brother claims today. The TV cook was falsely portrayed as 'permanently drug-dazed' and 'addled by narcotics', Dominic Lawson says. The court did not let her present evidence to defend herself, treating her instead as an 'object to be paraded and tormented' during ten hours of cross-examination as a key prosecution witness. Miss Lawson admitted taking cocaine seven times. She admitted she had also smoked cannabis during the collapse of her 'doomed' marriage but insisted she was not a long-term or habitual user. She said she had been drug free since leaving the relationship. Writing in today's Daily Mail, Mr Lawson likened her treatment to the burning of heretics in the Spanish Inquisition and warned the 'vicious' treatment of prosecution witnesses was a threat to British justice because it could deter future witnesses from giving evidence. He said his sister was 'heroic' in the face of such treatment but that the circus surrounding the fraud trial of her former aides had left the public under the impression she was the defendant. Lawyers for Miss Lawson's former housekeepers Francesca and Elisabetta Grillo questioned the 53-year-old about her drug use in an attempt to show she sanctioned the sisters' Pound685,000 spending in return for their silence. Giving evidence at Isleworth Crown Court in West London, Miss Lawson said she had faced 'a long summer of bullying and abuse' which she said had been 'dedicated to salvaging Mr Saatchi's reputation and savaging mine'. She said she had been made to feel she was on trial without any legal protection or representation, adding: 'I did my civic duty, only to be maliciously vilified without the right to respond.' Her brother said she had been given no advice or support by the CPS and - as a witness and not a defendant - was not entitled to a lawyer to represent her. Mr Lawson said: 'I would say that her conduct in the witness box was heroic. It was especially heroic given the way what was meant to be a formal examination of transactions by two employees had turned into a media circus - or rather an auto da fe - with this prosecution witness as the object to be paraded and tormented. He added: 'The process of justice is seriously damaged if the system makes testifying intolerable for prosecution witnesses.'