Latest figures show more than 100 people go missing in Australia each day, but most are found within a week.

Despite being missing now for more than 22 years, NSW Police won’t put Marion Barter back on the Missing Person’s register, after she was removed in 2012.

According to Australian Federal Police, in excess of 38,000 missing person reports are made to police each year, but only about 2,600 have been missing for more than three months.

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No regrets

Leading investigator into Barter's case, Byron Bay Detective Senior Constable Gary Sheehan, says it was his decision to remove her from the database.

Sheehan said with all the information he had obtained about the case, circumstantially it painted a picture that Marion Barter decided “to estrange herself from the family for whatever reason and get on with a new life”.

“I don’t know what goes through people’s minds when they make decisions such as these, that is to start a new life for any reason they decide,” he told 7NEWS.

“I mean, you have to remember, prior to going to England, again, she applied for a passport with a complete name change, didn’t tell anybody, travelled overseas as if nothing had happened in regards to that.

“So if you look at it from the perspective of a person who had gone to that length of trouble to do that before she left, it just seems to be a step in the same direction.”

"'So if you look at it from the perspective of a person who had gone to that length of trouble to do that before she left, it just seems to be a step in the same direction'. "

While acknowledging some inconsistencies to this - like Marion’s call to her daughter from the UK just a day before she allegedly re-entered Australia - Detective Sheehan said her actions were of somebody who wanted to go missing.

“I know for a fact she applied for this passport in a new name and, for whatever reason again, she decided not to tell the family she had done that.

"And (she) actually travelled overseas on that passport.”

Protocol

Australian missing person expert Dr Shaunagh Foy said police had to sight and identify a missing person before taking them off the missing person database.

But NSW Police said protocol and procedure was still followed when Barter was removed from the database because the circumstances into her disappearance were considered “extraordinary”.

“Page 18 of the NSWPF Missing Person Standard Operating Procedures allows officers to seek approval from the manager of the Missing Persons Unit to withdraw a case from the register, in extraordinary circumstances,” NSW Police Force said in a statement.

“This was done, based on the evidence available to investigators at the time, a decision authorised and approved by Gary's superiors as per the normal chain of command.”

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Help

If you have any information about Barter, email us in confidence: theladyvanishes@seven.com.au.