Rebekah Brooks has been granted special status at the Leveson Inquiry into press standards.
The former News International chief executive was named as a "core participant", someone who has a significant interest in the hearings or may face criticism.
The move means she will have advance access to documents and witness statements, and the right to put questions to other witnesses through her lawyers.
But Lord Justice Leveson rejected an application for actor Hugh Grant to remain as a core participant in the inquiry's next section.
Brooks will give evidence to the inquiry as it moves into its third module, looking at relations between national newspapers and politicians.
She applied for core participant status for the first module but was turned down.
Lord Justice Leveson said in a ruling today: "On balance, I am persuaded that it would be right for me to confer upon her the additional rights which accrue with core participant status, including early access to documents, advance sight of witness statements (in confidence) and the right to make submissions (if so advised).
"Accordingly, subject to the appropriate confidentiality undertakings, I grant her application."
Brooks, who edited the News of the World and The Sun, has twice been arrested by Scotland Yard detectives investigating allegations of phone-hacking, corrupt payments to public officials and an attempt to pervert the course of justice. She was bailed and has not been charged.
Lord Justice Leveson also granted core participant status for module three to MPs Chris Bryant, Simon Hughes, Tessa Jowell, Denis MacShane, Claire Ward and Tom Watson, as well as to former deputy prime minister Lord Prescott and former MP Evan Harris.
The inquiry finished sessions yesterday for its second module, examining relationships between journalists and the police, and will resume on April 23 with evidence from newspaper proprietors.