Under a Bill published yesterday by the Scottish Government, those who can "afford" to pay towards criminal legal aid will have to do so.
Currently, contributions in Scotland are only made in civil cases.
The Scottish Government has published draft legislation with the aim of saving £3.9 million from the legal aid budget.
Those with a disposable income of more than £68 a week would have to make financial contributions regardless of the offence they are accused of, according to proposals in the Scottish Civil Justice and Criminal Legal Assistance Bill.
Above the upper limit of a disposable income of £222 a week, assistance will only be given if the board considers it would still cause undue hardship to pay.
The Herald originally revealed, in 2005, that changes would be made to the system.
Justice Secretary Kenny MacAskill said: "On legal aid, the Scottish Government believes it is right and proper that those who can afford to pay towards the cost of their legal defence costs do so.
"We shouldn't have a system where those who can afford to contribute to the cost of their legal fees get taxpayers' cash at the expense of those who simply cannot afford to pay."
The Government said yesterday about 80% of people accessing aid would continue to pay nothing.
However, the Law Society of Scotland warned solicitors should not become "state-sponsored debt collectors".
Under the Bill's proposals, solicitors would have to collect the contributions of individuals in summary cases.
The Scottish Legal Aid Board (Slab) currently collects the majority of civil contributions.
Ian Moir, a member of the Law Society's criminal legal aid negotiation team, said: "We absolutely agree that people who can afford to pay a portion of the cost of their legal aid should do.
"However, we have a number of serious practical concerns, particularly around how contributions will be collected.
"The collection of contributions for criminal legal aid should be undertaken by the Slab and not by solicitors or their firms.
"The financial and administrative burdens on solicitors will be significant at a time when they are feeling the impact of the budget cuts that the Scottish Government made.
"More than 95% of contributions in civil legal aid cases are collected by Slab, so it would be consistent for them to collect contributions in all criminal legal aid cases as well.
"We simply do not believe that solicitors should end up being large-scale, state-sponsored debt collectors particularly when Slab already has structures in place to carry this out."
The Bill is part of a four-year Government plan called "making justice work".
The Bill also aims to establish a civil justice council to replace the Court of Session Rules Council and Sheriff Court Rules Council.
It would have a policy role to advise and make recommendations on improving the civil justice system.