Bank of Ireland's ICS Building Society has become the first mortgage lender to tighten the rules for solicitors for both home and commercial property lending.
The move follows boomtime abuses by solicitors such as Michael Lynn and Thomas Byrne.
In an email issued to mortgage brokers in recent days, ICS said it would no longer accept undertakings from solicitors who were backed only by the profession's so-called Assigned Risks Pool, a safety net for solicitors who have failed to raise professional indemnity insurance.
ICS also said it would now demand proof from solicitors that they held indemnity insurance "for all home loans irrespective of amount".
ICS said it was the first lender in the industry to change its requirements following a change in the Law Society's own rules and that it expected other lenders to follow its lead.
The building society said it would require all solicitors to show proof of their insurance "prior to any drawdown of funds".