Former News of the World editor Andy Coulson appeals today against a High Court decision that News Group Newspapers (NGN) does not have to pay his potential legal costs over the phone-hacking affair.
Coulson, 44, who resigned in February 2007, has sued NGN over the construction of a clause within a severance agreement.
He wants a declaration that NGN, which stopped reimbursement in August last year, "must pay the professional costs and expenses properly incurred" by him "in defending allegations of criminal conduct" during his tenure.
Coulson, who has always denied any wrongdoing, resigned from his position as Prime Minister David Cameron's director of communications in January last year, saying that coverage of the scandal was making it too difficult for him to do his job.
At last December's High Court hearing, NGN's counsel told Mr Justice Supperstone that the clause covered the "occupational hazards of being an editor" and not alleged criminal activity.
The hearing in the Court of Appeal before Lord Justice Laws, Lord Justice Sullivan and Lord Justice McCombe is expected to last half a day.