Defending his controversial plan to end the absolute need for corroboration - evidence from two sources - in criminal trials, he told MSPs: "Put simply, the requirement for corroboration has failed Scotland. It was formulated in a different age, before DNA, before CCTV. Times have changed."
There was criticism of the Conservatives for bringing forward the debate when the Bill containing the proposal was being tested in committee.
Conservatives Justice spokeswoman Margaret Mitchell insisted corroboration was "at the very heart of the Scottish criminal justice system" as she said High Court judges, the Law Society of Scotland, the Faculty of Advocates and the Scottish Human Rights Commission were all against its abolition.
For Labour, Justice Committee vice-convener Elaine Murray said: "I don't think this is an issue that Parliament should take a decision on based on less than 90 minutes' debate.
"The Justice Committee will take evidence in two sessions in November and December, and it is at the end of stage one that this decision should be taken."
Holyrood Justice convener, Christine Grahame of the SNP, vowed to abstain from the Government's proposal.