The government has ruled out a change in the law on assisted dying after a high-profile case involving an 80-year-old Bucks man with motor neurone disease.

Geoff Whaley, from Chalfont St Peter, arranged to end his life at a Dignitas clinic in Switzerland to avoid a protracted death from the disease, which he was diagnosed with two years ago.

His wife Ann, 76, supported his decision but was interviewed by Thames Valley Police over her involvement in his plans.

Officers dropped the case but the couple called for the law to be changed to allow assisted dying in some circumstances.

In UK law, helping someone end their life is punishable by up to 14 years in prison.

Raising the case in the Lords at question time, independent crossbencher Baroness Meacher backed the call for a change in the law.

Lady Meacher said Mr Whaley died a "dignified death" last week but most people could not afford to take their family to Switzerland or get the medical report from their doctor to enable them to have such a death.

"In a civilised society someone in Geoff Whaley's position should be able to avoid months of being unable to swallow, unable to eat, to drink, to speak, to move, totally cut off from communication."

She urged ministers to discuss a change in the law. But Lord Keen of Elie, Advocate General for Scotland, told her: "It is not the intention of the Government to seek to change the law in this area.

"Every case has to be considered according to its own particular facts and circumstances. I readily acknowledge that many of these cases are extremely tragic."

Lord Keen said Crown Prosecution Service policy on assisted suicide provided guidance to prosecutors and set out the public interest factors that must be applied in reaching decisions.

"There are no plans to reassess the CPS policy in relation to such cases," he added.

Labour's Baroness Blackstone asked if it was a good use of police time to "interview the wife of a dying man who wishes to choose how he dies", and hit out at the "treatment of loving families like criminals".

Lord Keen said it was for the CPS to apply the law and not make the law. Police were bound to investigate what was potentially criminal conduct.

Leading lawyer and independent crossbencher Lord Pannick said there continued to be considerable uncertainty in the law, which was causing "enormous distress to those at the end of their lives and their families".

Lord Keen said the CPS published a policy document in 2010 and that policy was "working well at the present time".

But Tory Lord Sherbourne of Didsbury said that for terminally ill people, with no hope of recovery, the current law, which prevented them from being able to end their lives with dignity, is "condemning them to great and unnecessary suffering".

Lord Keen said the Government was conscious of the difficulties and challenges facing people with a terminal illness.

He said that of 140-odd cases referred in the last nine years to the CPS, there were prosecutions in respect of the Suicide Act 1961 in only four, resulting in one acquittal and three convictions.