The Scottish Conservative north-east MSP raised concerns following the announcement that criminal solicitors will no longer take on court appointments for those accused, without lawyers, who are not allowed to represent themselves.
The announcement from the Scottish Solicitors Bar Association comes as more than 100 lawyers and 40 legal firms quit Scotland's legal aid scheme amid a boycott over funding worries last year.
Alleged victims of crime are waiting up to four years for serious criminal cases to go to trial, with some losing hope and disengaging before their trials even begin.
Mr Kerr, a practicing solicitor, has spoken to criminal defence lawyers in Aberdeen who have outlined their concerns over the inadequate investment in legal aid.
He said victims of crimes such as sexual and domestic abuse are now having to go through additional pain and trauma due to the court backlog.
Ash Regan, Minister for Community Safety, dismissed the calls.
She said: “We are, of course, very concerned about the effect of the boycott on court users and on justice partners.
“Although the budget for legal aid cases is demand led, the Scottish Government allocates a budget to the legal aid fund. In 2021-22, that was £138 million, so the called-for 50 per cent uplift would add £69 million per year to the fund, which is unaffordable, given the current pressures on public finances.”