Police Ombudsman Marie Anderson has taken up her new role at the watchdog.
She has succeeded Dr Michael Maguire who retired on Monday after seven years in the high-profile job.
Ms Anderson is the fourth ombudsman to be appointed to the role.
She is a former Northern Ireland Ombudsman and was previously the Assistant Information Commissioner for Northern Ireland.
The Police Ombudsman’s Office deals with more than 2,600 complaints about the conduct of serving police officers annually.
It also has more than 400 complaints about matters linked to the Troubles.
The Office has an annual budget in excess of £9 million and employs around 150 people.
In a statement she said that people want the police to be held to account.
“Some of the most significant issues in recent times in Northern Ireland have been about the performance of our public services and officials.
"People demand accountability from those who serve us,” she said.
“In my experience, when any process for investigating complaints cannot evidence the independence and impartiality of its findings, the public will lose confidence in it.”
Ms Anderson said she will be “looking at the Office’s complaints and investigation procedures to ensure they are fair and underpin its independence”.
“I want to satisfy myself that the processes for investigating complaints about police are as simple and accessible as they can be for the user and ensure transparency and learning for the PSNI.”
In an interview with the Irish News this week former ombudsman Michael Maguire said some in the “policing family” have difficulty with accountability and likened the oversight role at times to “trench warfare”.
