The former inspector of constabulary said people may be “more fearful of stepping forward to report loved ones missing” after the “gross invasion of privacy” suffered by Nicola Bulley and her family.
Zoe Billingham made the remarks after receiving her CBE from the Princess Royal at a Windsor Castle investiture on Tuesday.
The body of 45-year-old Ms Bulley was pulled from the River Wyre in Lancashire on Sunday after she was last seen on January 27.
Lancashire Police has been criticised for its investigation into her disappearance, including why it released some aspects of her private life into the public domain.
Ms Billingham, who independently assessed police forces in her former role, told the PA news agency: “It’s definitely not my job to judge Lancashire Police, but what I would say is what we’ve seen over the last few days is a gross invasion of privacy.
“And my message to women out there would be that if your loved one, if your mum or your sister went missing, what we’ve seen over the last few days is not okay, it’s not what we would ordinarily see in a missing persons investigation.
“I would hope that it wouldn’t put or deter people from contacting the police when their loved ones go missing and I know that people will be more fearful of stepping forward to report loved ones missing if they think that deeply personal private information is going to be pored over, assessed and in the public domain.
“That’s now how it should be and not how it usually is and I think the police need to make sure they make that clear to the public.”
She said it was “lovely” to meet the Princess Royal at the investiture and that they discussed the work Ms Billingham has been doing to “help reduce violence against women and girls”.
She added: “Because that’s really been one of my primary roles in my job as a police watchdog and of course that’s such an important and newsworthy issue right now.
“And she was very interested in the work that is being done to reduce violence against women and girls which is great.
“I’m really pleased there was a huge package of measures announced by the Prime Minister and the Home Secretary yesterday that puts fighting violence against women and girls at the forefront.
“And to be treated as seriously as tackling terrorism, and I’m delighted that that’s happened.
“It was a recommendation I made in the last report that I made as Her Majesty’s inspector of constabulary.
“And it shows the public and particularly women that policing will mean business in terms of keeping them safe, so it’s apposite that today I’m here at the palace receiving recognition for work with so many others that I hope will lead to a sea change in the way police deal with vulnerable women, women who are experiencing abuse of any type.
“And I think hopefully in time that will lead to the public beginning to regain trust in the police.”
She said she is “thrilled an honoured to have been given this recognition” of a CBE.
