The number of solicitors withdrawing from legal aid schemes in police stations has quadrupled in three years, according to figures.
A freedom of information request found 272 lawyers withdrew from police station rota duty to supply aid in 2018.
The FOI request, made by the Scottish Liberal Democrats, indicates the 2018 figure is well up on the 64 withdrawals recorded in 2017, and the 69 in 2016.
Aid is provided in Scotland to ensure advice can be supplied to suspects who may not otherwise be able to afford their own legal costs.
In January, the implementation of Part One of the Criminal Justice (Scotland) Act 2016 meant everyone in custody has a right to legal advice.
Previously, only those being interviewed by police had the right to speak with a solicitor.
There have since been claims that the increased workload is not manageable for those working in the profession.
The Government knew that the rules which came into force in January would lead to significantly increased workloads
Large numbers of the withdrawals from police station duty plans were in Aberdeen, Dundee, Edinburgh, Glasgow and Livingston.
Scottish Liberal Democrat justice spokesman Liam McArthur said: “The number of solicitors withdrawing from this legal aid programme has skyrocketed. The scale of the departures show that legal aid as it currently operates doesn’t work for those tasked to provide this critical service.
“The Government knew that the rules which came into force in January would lead to significantly increased workloads.
“There was cross-party support for giving everyone being questioned in a police station the right to legal advice. However, the failure to resource and prepare properly for this has led to many professionals having to opt out.
“Legal aid provision is becoming more fragile by the day. In some areas people have to rely on telephone advice. That’s not good enough in a 21st century-legal system.
“Capacity is a serious concern. Ministers need to step in and resolve this.”
A Scottish Government spokesman said: “Unlike in England and Wales where legal aid provision has been intentionally and dramatically cut, the scope of legal aid in Scotland remains extremely wide.
“The introduction of the Criminal Justice (Scotland) Act 2016 represents one of the most significant changes to police procedures in Scotland for at least a generation, modernising arrest, custody and questioning procedures and improving access to legal advice for people in custody.
“Regulations approved by the Scottish Parliament are delivering an enhanced fee package for solicitors providing police station advice. The scheme, underpinned by the Scottish Legal Aid Board, is voluntary, with solicitors putting themselves forward to provide advice for those held in police stations.
“It is essential no individual is denied access to their right to legal advice delivered by employed solicitors who currently provide the service and private solicitors who opt to remain on the duty scheme.”