CSV, which last week was awarded a £7.3m grant to help mental health patients, cleared Hatter to work as a volunteer.
Less than a month later, Scope ordered Hatter to leave when a resident accused him of conning him out of £40. Further investigations by Scope uncovered previous allegations of sexual misconduct against Hatter.
In a statement last week, Scope said: "We have temporarily suspended recruiting additional CSV volunteers in our residential service centres.
We are conducting a full and proper review, which will determine our future policy.
"We have also worked closely with the police to conduct security audits at all of our residential services and have now put in place any recommendations."
CSV, which is the UK's largest volunteering organisation, has worked with more than 3,000 offenders and ex-offenders over the past 35 years.
Hatter applied to work as a volunteer while serving a prison sentence for a series of thefts and burglaries at charity shops.
"He was interviewed, we took up two references and had a full police check," said CSV spokesman Jason Tanner. He added that the checks only uncovered crimes against property.
"As a result of the incident, CSV launched a review of its procedures in relation to the placement of this volunteer," said Tanner. "As a result of our review we have taken measures to strengthen our risk-assessment processes for vulnerable volunteers in collaboration with those who provide volunteering opportunities."
Scope had recruited CSV volunteers to its 38 residential centres, which house 520 people with cerebral palsy, since 1999. Those taken on before last week's suspension will continue to help out pending the outcome of Scope's review.
Although residents have 24-hour access to staff, the charity aims to provide as much independence as possible. "The need for the highest standards of security should not detract from residents feeling as if they are living in as normal an environment as possible," said the Scope spokeswoman.
Judge Gareth Hawkesworth said Hatter had shown "brutal violence" and "unimaginable cruelty".