Mae yna gorff cynyddol o dystiolaeth ac ymchwil ledled Cymru a'r DU a gasglwyd gan awdurdodau lleol, gwasanaethau cynghori ar ddyledion a sefydliadau eraill, sy'n cwestiynu effaith ac effeithiolrwydd anfon rhywun i’r carchar am beidio â thalu treth gyngor.
There is a growing body of evidence and research from across Wales and the UK, collated by local authorities, debt advice services and other organisations, which questions both the impact and effectiveness of imprisonment for non-payment of council tax.