Evelyn MacPherson (71), who has worked at the Brook Street store for 17 years, said staff got a “stay or go” ultimatum from their volunteer co-ordinator last week after the introduction of a new Prison Volunteer Scheme.

Mrs Macpherson, who said she was speaking on behalf of all the female volunteers, has devoted a large part of her life to the charity, not only working and managing at the shop, but taking part in sponsored walks, donation pick-ups, bake sales and other fundraisers. One year, she asked family and friends to give her money rather than birthday presents so she could donate the cash to Sue Ryder.

The news that offenders are to work in the shop was met with shock by most of the volunteers, who claim there was no room for negotiation.

Mrs MacPherson was so distraught she was moved to tears.

She said, “On Wednesday we were told we were to be getting people from Castle Huntly who were on release on temporary licence.

“The volunteer manager told us it was happening and if we didn’t want to work with them then we would be shown the door.

“The majority of us are in our 70s and 80s and are really concerned. We don’t want to have to work with them.”

The charity outlet has around 20 staff, almost all over 60 and some in their 80s.

Some have been there for years and the routine has become an important part of their everyday lives.

Mrs MacPherson said, “I have been very upset and I have been crying. I love going in there and I’m there all the time.

“We were assured we wouldn’t be working with rapists, child molesters, paedophiles or serial abusers, but were told we could get murderers, drug abusers or fraudsters. I would be frightened to work with some of these people and I certainly wouldn’t want them finding out where I live.

“But what would be to stop them finding out where I stay?”

Some customers are said to have already boycotted the charity over the new policy and have stopped bringing in donations.

Mr McPherson said, “It seems all our willing service counts for nothing.

“Customers have been upset and declared that they would no longer support the charity with donations or custom. Our human rights are being completely disregarded.”

Tracey Mealing, head of volunteering at Sue Ryder Care, said the work placements could be stopped at any time if issues arose.

She added, “We appreciate people may have concerns about the Prison Volunteer Scheme we are using in some of our shops and we have set up training sessions to address and respond to volunteers’ questions.

“Prisoners who volunteer at Sue Ryder Care have been through a robust and rigorous risk assessment process with the Prison Service to ensure the safety of Sue Ryder Care staff, its volunteers and supporters.

“All prisoners who volunteer for us have undertaken rehabilitation and are deemed suitable to be placed in voluntary placements in the local community and are released on a temporary licence.”

The Scottish Prison Service confirmed inmates from Castle Huntly are “vigorously assessed” before going out and such placements have been taking place in communities for around 15 years.

A spokesperson said, “Individuals undertaking supervised work placements have undergone extensive risk assessment. The SPS places great importance on preparing prisoners for release, and undertaking work placements is one way of testing prisoners prior to their release.”

It is thought the Sue Ryder shop in Dunblane will be drafting in female inmates from Cornton Vale prison in Stirling.