The Churches Child Protection Advisory Service has said it is "very pleased" with the statement from the Archbishop of Canterbury on child abuse following last week's sentencing of Peter Halliday, the ex-choirmaster who abused boys between 1985 and 1990.

The Church of England faced fierce criticism last week for failing to report Halliday to police when church authorities were first made aware by the parents of one victim in 1990.

CCPAS called Dr Rowan Williams' statement "timely", after he expressed his "deep sorrow over the suffering experienced in child abuse cases involving the church".

The Diocese of Bath and Wells, meanwhile, expressed its shock yesterday after Bristol Crown Court sentenced the vicar of St John the Evangelist in Clevedon, North Somerset, 52-year-old Rev David Smith, to five-and-a-half years in prison for sexually abusing boys under his care .

"We are shocked and horrified that he has fallen so far short of the very high standards expected of priests in the Church of England," said a statement from Bath and Wells Diocese yesterday.

In an open letter to the Archbishop, CCPAS Executive Director David Pearson said his organisation was "aware of the hard work of so many within the Church of England to safeguard children".

However, Mr Pearson explained that as a result of media enquiries following the recent Halliday case, "it has been necessary for us to challenge some of the statement made by the Church of England ... which suggested that things were somehow 'very different' in 1990 when these particular concerns first came to light."

He added: "Various spokespersons for the Church of England referred to the Government guidance 'Safe from Harm' issued in 1993. This was about the safe recruitment of workers and did not directly address the issue of reporting crimes against children. However, I accept that clergy were not sufficiently aware of their responsibilities at the time."

Mr Pearson, who was sexually abused himself by a youth leader in the 1950s, said that on discovering the situation local leaders immediately reported the matter to the police.

"I have been involved in child protection issues as a social worker and social work manager over a 40-year period. The expectation regarding reporting serious crimes has never been any different although, as we know, until denominations and others issued proper child protection guidance many churches failed in their responsibilities to act appropriately in such cases.

"Having looked at numerous historic cases over time, it is quite clear to me that the dominating factor has been the desire to protect the interests of the church; the needs of children have not properly or adequately been addressed."

He said it was "very unfortunate" that despite the introduction of policies and training in the 1990s, "those who have been involved in failing to report such matters were not able to reflect on past decisions and discuss such matters with the statutory authorities."

Mr Pearson stressed that "it is never too late to act in these sorts of cases" and urged the Archbishop to do everything in his power to persuade diocesan authorities to address the issue of child abuse, and more specifically, to re-open old files and re-examine "any historic instances where cases of abuse have possibly been hushed up". He said the discovery of possible cases of abuse should be reported to the police "as soon as practicable".

"This is the only way to obtain justice for those who have been abused and to help them come to terms with what happened to them. It will also send a clear signal to any others tempted to abuse children within a Church of England setting that senior Anglican clergy will not tolerate such behaviour - and will ensure that all allegations of abuse, no matter how long ago they took place, will be properly and fully investigated."