Rudi Vis, MP for Finchley and Golders Green, has cost the taxpayer more than £17,000 since the 2001 general election by asking 128 parliamentary questions on prisons.

This represents two-thirds of all written questions submitted by the Labour MP since July 2001, and Barnet Council's leader, councillor Brian Salinger, said this week that his constituents would be right to feel "bemused" by the figure.

Research has revealed that many of the answers have ended up in papers or press releases issued by the lobby group the Howard League for Penal Reform HLPR, and since last May's general election all 26 of Dr Vis's written questions submitted to ministers have centred on criminal justice.

Mr Salinger said: "I am sure that Dr Vis's constituents will be as bemused as I am about the number of prison-related questions he is asking."

Dr Vis is a member of the HLPR, headed by Frances Crook, a former East Finchley Labour councillor and a friend of the Dutch-born MP. "I have an understanding that I will ask specific questions for HLPR," said Dr Vis said.

Asking questions on behalf of an organisation does not break any parliamentary rules.

He defended his record by claiming that he had written many more questions on a range of issues to ministers in personal letters, which were not included in the official list.

The average cost to the taxpayer of a written question is £134, and Dr Vis has tabled 128 on prison and similar issues, totalling £17,152.

When it was suggested to Dr Vis that his constituents may see his prison-related questions as irrelevant to them and a waste of taxpayers' money, he said: "It is very difficult for me to disagree or agree.

"I write quite a large number of letters about Iran.

"It is of interest to people in the constituency because of Israel.

"I have written letters on Cyprus it is maybe not significant, but we have 4,000 people who hail from Cyprus in the constituency."

Parliamentary figures also reveal that Dr Vis has only spoken once in a debate since the general election, which places him 614 out of 645 MPs in terms of verbal contribution.

But the MP for Margaret Thatcher's old seat said that he did not want to waste parliamentary time by repeating what other MPs had said, and did not want to offer his opinion on issues that he did not know well.