Though violent crime can have a devastating effect on the lives of people, sometimes the less serious offences can be just as traumatic for victims.

Doorstep fraud involving bogus workmen or officials - particularly when the sufferers are elderly - can have a terrible and long-lasting impact.

One such serial offender brought misery to large numbers of older people in Glasgow in the 1980s.

And in an unusual twist, the prime suspect was a woman.

The offender in this case had been dubbed in the media as ‘Smoothie Susie’.

She was a bogus caller who duped her mainly elderly female victims out of large sums of money.

Smoothie Susie would arrive at their doors pretending to be someone in authority and there to help them.

She posed as a social worker, home help, council employee, Government official or any other role that would gain her the trust of her unsuspecting victims.

The conwoman would chat nicely to the householder using her skills to give her an air of authority and knowledge of caring.

Her prey would relax and trust her.

Some victims were pretty much housebound.

Smoothie Susie would make sure they were tucked up in bed each night, before waving them goodbye.

As a result, all the elderly people she conned were convinced that she was a decent and caring person.

Only later would they discover that cash was missing from a handbag or purse, or a drawer had been ransacked.

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Smoothie Susie first came to the attention of police in Glasgow in May 1984 when she targeted a 94-year-old woman.

Posing as a social worker, she stole her victim's purse containing £143.

Her reign of terror escalated as she targeted victims across the city.

Anyone from their late 60s to mid-90s fell victim.

The victims were well chosen but police did not know how or why they were targeted so easily.

At one point they wondered if it was the same person committing the crimes, as the descriptions of the suspects varied.

It was only later that they discovered Smoothie Susie was changing her hair colour each time.

A crackdown called Operation Prey was set up based at Craigie Street police office in Govanhill.

By October 1985, police had more than 30 similar crimes.

Police tried to flush out the conwoman with a press and TV appeal.

A photofit of her was also circulated widely.

Every time there was media appeal the crimes would stop then start up a few weeks later.

She struck from one end of the city to another, from Bearsden to Partick to the Southside.

Invariably the bags and purses would be found by members of the public, dumped at various locations with the cash missing.

However, other items like pension books and credit cards were usually left.

The police thought they had got a breakthrough when they arrested a man who had tried to use one of the stolen credit cards, but it turned out he had found it in one of the abandoned bags.

Then suddenly the police got a much-needed break.

One elderly woman said that the bogus caller had handled a photo frame and left a thumbprint.

However, there was no match in the system.

The man leading the investigation, detective inspector Bryan McLaughlin, realised that the conwoman must have some form of medical background due to her knowledge of the care system.

He and his team went round hospitals in the city showing staff the photofit, but no one recognised it.

McLaughlin even compiled a giant map showing all the locations of the different crimes in the hope they could work out where Smoothie Susie might strike next.

Graphs outlined the pattern of her movements, but without the necessary computers to analyse the data they were not much help.

However, they did notice that many of the stolen bags were being dumped in the East End of the city, suggesting that Smoothie Susie lived there.

The woman had been using fake names, including that of a woman detective who was working the Smoothie Susie probe.

She remembered a female she had arrested back in 1974 for an identical series of bogus caller crimes.

The alleged conwoman had not been convicted so her convictions were not on file.

However now they knew her real name - Wilhemina Watson.

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Watson was a nursing sister in her mid-50s, married with three children, and based at the nearby Victoria Infirmary in Glasgow.

Cops realised she was using her position to target vulnerable older people.

She would scour hospital records to find the home addresses of women living on their own, often with no family.

They checked her shift rota and discovered that all the thefts had taken place on her days off.

They then realised that one of the stolen bags had been found near a cemetery where her mother was buried.

DI McLaughlin decided to set up surveillance operation to try and catch Watson in the act, by tailing her from her home in her car.

On the first day they caught her trying to get into the home of an elderly woman in Rutherglen.

Police swooped and arrested the nurse.

Watson was charged by the police but continued to offend even after being given bail by the courts.

Her areas of attack increased and she began striking across the central belt into Largs, Renfrew, Stenhousemuir and even Edinburgh.

Watson was re-arrested by police and she was charged with offences over a four-year period.

Their one worry was how many victims would still be alive to give evidence as some had already died.

Police reckoned that Watson had committed up to 400 crimes between 1984 and 1988.

The 54-year-old was charged with 90 cases of fraud, theft and attempted theft which had netted her around £2700.

In reality, her bogus caller scams had probably earned her much more.

Watson was eventually prosecuted with 33 crimes and stood trial in July 1988 at Glasgow Sheriff Court and pleaded guilty to 24 of the charges.

The court heard that her first victim, an 84-year-old, was robbed within 10 minutes of her entering the home, where she had posed as a home help.

Another walked with the aid of a walking stick and was even asked to point out the home of the next victim Watson planned to rob.

Watson then stole £900 in cash from that woman, money which she had saved up for a new suite.

Her oldest victim had £70 stolen from a purse, while Watson posed as a Government benefits worker.

Watson’s lawyer argued that the crimes were out of character even though she had been investigated almost 15 years earlier for the same offences.

The sheriff took pity and deferred sentence for a year on the grounds that she seek psychiatric help and repay her victims.

A year later she was formally admonished.

Reflecting on the case in his 2012 book Crimestopper, McLaughlin, now retired, said: "To my mind Smoothie Susie showed no remorse and was only in it for the money.

“When we charged her she was non-communicative.

"She later told the newspapers that she did not know why she had done it and said she spent the money on everyday things.

"Her husband insisted that she was not evil, just in need of help."

McLaughlin also expressed concerns at the lack of action by the Victoria Infirmary at the time when he had raised concerns with senior management that it may be an employee there.

He added: "They dismissed my concerns out of hand even though she had been right under their noses."

McLaughlin recalled one of the victims who had lived in Partick and was over 90.

She broke down when she explained that a wedding ring belonging to her late husband had been in the bag which had been stolen alongside the cash.

McLaughlin then decided he would try and see if he could track down.

He discovered it had been handed into the police lost and found by a young woman who was allowed to keep after six months.

The woman had thrown out the bag but kept the ring she found inside, realising it might be of value to someone.

He added: “I took the ring to the woman's house and her face lit up when she saw it.

"That was one of the most rewarding moments that I had in my police career.

"Seeing that delighted woman's reaction was worth more than [a] million pounds and added to the satisfaction of nabbing the notorious Smoothie Susie."