A SEX offender who carried out a string lewd sex attacks over a 38 year period has been jailed.

William Hislop, 53, targeted the male and three females, who are all now adults and can’t be named for legal reasons, between 1977 and 2015 at an address in Renfrew and in Neilston, East Renfrewshire.

Police were told in 2004 he’d abused his second and third victims and he was interviewed twice over his crimes.

It was ruled there was not enough evidence to prosecute him and he was left free to abuse his fourth victim, who is disabled, in Neilston in March last year.

But justice eventually caught up with him and he was handed a sentence totalling six years and 11 months at Paisley Sheriff Court on Friday.

He was jailed for 53 months – four years and five months – and will be monitored for 30 months – two and a half years – once released into the community.

Hislop pleaded guilty to four charges, one in relation to each victim, earlier this year.

He abused his first victim between 1978 and 1980in Renfrew when his victim was aged between eight and 10 and he was 16 or 17.

He abused his second victim on an occasion between 1977 and 1980 when she was asleep and was aged between 12 and 14, at the same address.

His third victim was abused between 1994 and 1995 at another address in the burgh town.

He told the nine-year-old he had a surprise for her before entering her bedroom, watching her getting changed and assaulting her.

The embarrassed schoolgirl told a friend what had happened but couldn’t tell her mum and wrote it in a letter, which was found by her mum years later.

Procurator fiscal depute Scot Dignan, prosecuting, said: “This was reported in 2004 and was initially investigated but there was insufficient evidence to proceed.

“He was interviewed again in 2011 but, as indicated, there was insufficient evidence to proceed.”

Hislop went on to abuse his fourth victim in March 2015 at his home in Neilston.

He was drinking with the 19-year-old and her boyfriend and struck when her boyfriend fell asleep, despite her crying and telling him to stop.

She told her boyfriend the next morning and they contacted police a few days later.

The 2015 assault meant there was now enough evidence to prosecute Hislop over the abuse of the other two women in the 70s and 90s.

And as part of their investigation police discovered he abused the boy in the late 70s.

Hislop, who had long hair when he admitted his guilt but has since shaved his head, pulled faces as his crimes were explained in court.

Sentence was deferred for him to be assessed by social workers and a psychiatrist and he returned to the dock on Friday to learn his fate.

Defence solicitor Gordon Ritchie asked for leniency, saying Hislop’s guilty pleas saved his victims from “the distressing and harrowing process of giving evidence”.

The lawyer added: “Children learn from their parents’ behaviour and boundaries and such behaviour was a feature of Mr Hislop’s childhood and upbringing.

“If ever there was someone suitable for education and supervision, due to his age and lack of previous convictions, Mr Hislop would be the perfect candidate.

“He is not in my submission a danger to the wider public due to the length of time since the offences and the individuals involved.

“By sending him to prison your lordship would not be properly protecting the public. He has been ostracised by his family.”

But Sheriff Seith Ireland ruled there was only one way he could deal with Hislop.

As he jailed him for the “serious sexual offences”, he said: “I’m left with the opinion that no other disposal is appropriate other than a custodial sentence.You remain and present a serious risk to the public because of your behaviour of offending in a sexual manner.”