A deaf couple are to face trial next month accused of mounting a four-year scam to defraud taxpayers of nearly £250,000 by submitting bogus claims for sign-language interpreters.

Andrew and Caroline Thomson are said to have claimed for sign-language interpreters they did not need - including one for a business trip by Andrew to Las Vegas - and employed a company that they themselves owned to supply them.

The husband and wife, who ran online interpretation services for the deaf, are said to have formed a fraudulent scheme to obtain funding, to which they were not entitled, to pay for British Sign Language (BSL) interpreters under the Government's Access to Work Scheme.

It is alleged that between April 1, 2008 and November 30, 2011 they pretended to the Department of Work and Pensions that Andrew Thomson himself needed the services of BSL interpreters eight hours a day, five days a week, so he could carry out a self-employed job at his company Sign-now.com; that Caroline Thomson needed similar BSL interpreters six hours a day, five days a week, so she could carry out a self-employed role at another business, Online Advocacy Services; and that a third person self-employed at Sign-now.com, Dean Humphreys, also needed interpreters six hours a day, five days a week - the truth being that none of them required or actually received that level of assistance.

It is further alleged that the Thomsons failed to disclose to the DWP that the organisation they had engaged to supply the BSL interpreters - The Interpreting Agency Limited - was in fact wholly owned and operated by themselves.

The couple are said to have submitted invoices from The Interpreting Agency Limited to the DWP for thousands of hours of interpreting and translation services - invoices that they had prepared themselves, and that did not represent the true total number of hours of interpreting provided.

It is said they backed these up with monthly claim forms, thereby inducing employees of the DWP to pay them £238,352, which they obtained by fraud.

Andrew Thomson faces a second charge alleging that he submitted a false claim for the expenses - travel, food and accommodation - of a BSL interpreter he said accompanied him on a trip to a trade fare in Las Vegas in July 2010, the truth being that no such person accompanied him or provided him with any such services.

It is alleged that in this way he obtained a further £1,912 by fraud.

All three companies involved in the alleged scam were based in the Grangemouth Enterprise Centre, Falkirk Road.

At Stirling Sheriff Court on Tuesday, lawyers for Andrew Thomson, 51, and Caroline Thomson, 52, of Stephens Croft, New Carron, Falkirk confirmed the couple maintained their pleas of not guilty to all the allegations.

Solicitor Murray Aitken, for Andrew Thomson, said any trial was likely to take "at least three to four weeks".

Addressing the couple through a BSL interpreter provided by the court, Sheriff William Gilchrist ordered them to appear next at a further procedural hearing on March 15, before a special jury sitting scheduled to start on March 29.