Last week, Jeffrey Ash was jailed for 40 months for smothering and setting fire to his 83-year-old mother Ellen.
The High Court was told he could no longer cope with Mrs Ash's terrifying hallucinations, her failure to recognise her son and the "onerous burden" of looking after her almost single-handedly.
Mrs Ash died in the house she shared with her son in Everard Drive, Colston, Glasgow just a week after she was sent home from hospital.
Donald Findlay QC told the High Court in Edinburgh: "Ash was left to do that which no son should have to do."
The court was also told Mr Ash had repeatedly told health care professionals he could no longer cope.
Mr Mason now wants an investigation and has written to Matt Kerr, the city council's executive spokesman for social work.
The carers' champion said he was deeply shocked but not surprised at the case.
He added: "There are dozens of carers all over Glasgow struggling to cope with caring burdens that stretch them to the limits of their strength and abilities.
"Nearly all of them are dealing with social work and health professionals who either do not understand the need to give them additional help or lack the means to do so.
"The only surprise is that more carers do not break under the strain."
Judge Lord Pentland told Ash: "No matter how difficult circumstances you had no right - as you acknowledge - to take her life."
He suggested first offender Ash's duty should have been to seek further support.
But Mr Mason said: "It is to Lord Pentland's credit that he recognised Mr Ash had been left in an intolerable and unsustainable situation.
"I don't know why he thought Mr Ash was in a position to "insist" on social work or the NHS doing something and I am sorry he did not say anything about the imperative need for the council and the Health Board to institute an independent investigation to find out what had gone wrong.
"I do not think it is good enough for Mr Ash and his sister to be left bearing their burden of guilt and grief while the professionals move on.
"As council Carers' Champion I think it is my duty to ask for an independent investigation."
A council spokesman said: "We will look closely at the circumstances of this case.
"However, we are clear extensive support was available to the Ash family but that this support was often declined."