The family of a wealthy pensioner murdered by her daughter’s boyfriend has reacted with fury after a judge described the killer as “kind and caring”.

George Maben, 45, was was jailed for a minimum of 13 years — two years less than the standard minimum term — after being covertly taped by police confessing to strangling the mother of his partner, Lucy Rees.

Maureen Cosgrove was said to be annoyed that he was living in her £700,000 home rent free and told him to wipe his feet, pick up his cigarette butts and not to leave his jacket lying around, the Old Bailey was told.

Maben, who is unemployed, strangled the 65-year-old grandmother of seven in her kitchen with a ligature and made it look like a burglary gone wrong.

A spokesman for Mrs Cosgrove’s family said: “They are absolutely disgusted. They are livid. You cannot overstate how badly they feel at this sentence today.”

Police were privately outraged at the sentence and prosecutors were considering whether to appeal against the sentence for “undue leniency”. One officer said: “You would get more for armed robbery with a knife. It is an absolute disgrace.”

Jailing Maben for life, Judge Jeremy Roberts, QC, said that the tariff was an “unusually low figure for pre-meditated murder” but that he felt entitled to pass down such a sentence.

“I am quite certain that this offence was the result of a very unusual combination of circumstances and that it is wholly unlikely that you will do anything like this again,” he said.

Judge Roberts said he did not believe that Maben “posed a significant risk of serious harm to the public” and praised his impeccable character.

“It is clear you are generally a kind and caring person and you have done a great deal of good, especially to people in serious problems who you have helped.”

The killer was under “enormous pressures” in the lead up to the murder, the judge said. He then prefaced his next remarks by saying that he did not want them to be “misunderstood” as criticisms of the “entirely innocent” victim.

“It wasn’t anybody’s fault that the situation developed in which your relationship with Lucy, who you loved deeply, and her mother, who you must have seen as an obstacle to you ever being able to enjoy the kind of life you wanted with the woman you loved and the mother of your child, drove you to such an act of desperation as this. The extent of your desperation is graphically demonstrated by your prayer for forgiveness which was covertly recorded by the police.”

He added: “The pressures you were subject to don’t begin to justify or excuse the taking of somebody else’s life but I am entitled to take them in to account and I do.”

Police bugged Maben’s car and were listening in as he said: “Please God help me, God forgive me or what I have done.” He added: “I just couldn’t take it any more. Every single day she was breaking me down. Please God will you forgive me.”

Maben, who was unanimously convicted of murder, and the previously married Mrs Rees had been together for two years and lived at Mrs Cosgrove’s five-bedroomed house in Surrey. Mrs Rees was seven months pregnant at the time with Maben’s son.

The court was told that the relationship between Mrs Cosgrove and Maben had not been a happy one. He was out of work and Mrs Cosgrove was frustrated that he was staying in her home for free.

Mrs Rees said: “They would argue over silly irrational things. He wouldn’t take his shoes off when he walked into the house.”

After a series of arguments Maben went back to live with his mother and was allowed only to stay at weekends.

On the day of the killing he took a bus to Mrs Cosgrove’s home. He strangled his victim and tried to make the killing look like a burglary that had gone wrong by taking Mrs Cosgrove’s handbag and throwing it into a neighbour’s garden.

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