ONE of the region's MPs has been fined £500 and ordered to issue an embarrassing apology after mis-using parliamentary expenses to send hundreds of letters to constituents.

A parliamentary watchdog found Stockton South MP Dari Taylor guilty of wrongly using pre-paid envelopes stamped with an official parliamentary crest for "party political" correspondence.

Worse, its report expressed bewilderment that Ms Taylor carried on the practice - despite being warned that it breached the strict rules on use of taxpayer-funded allowances.

The verdict was branded an "expenses abuse scandal" by James Wharton, the Conservative candidate for Stockton South at the next election, who lodged the complaints which triggered it.

But a defiant Ms Taylor insisted she had made a mistake "inadvertently" - and accused the Tories of pursuing the complaint in search of "a cheap headline".

The MP criticised the rules as confusing, pointing out that envelopes with a green Commons crest were allowed, but red ones with the famous Portcullis logo were not.

The Commons committee on standards and privileges was asked to investigate complaints about the use of pre-paid envelopes after 'street surgeries' in Stockton South last year.

The rules state that parliamentary allowances must only be used to "inform constituents about your work" - and not for "party political or campaigning material".

But some of the letters sent out by Ms Taylor referred to "the Labour government's youth strategy" and boasted about how "cash spending per pupil, which was £2,500 in 1997, will rise to £6,600 by 2010".

The committee concluded: "We strongly deprecate the continued misuse by Ms Taylor of House stationery for political purposes.

"We are surprised that an experienced member has repeated breaches of the rules and has failed to act in accordance with advice by the House authorities."

The conclusion is particularly damaging for Ms Taylor because Stockton South - with a slender Labour majority of just 6,139 - is a key Tory target for the next election.

Describing it as an "attempt to subvert democracy", Mr Wharton said: "This misuse of public funds places a serious question mark over her fitness for office.

"I have never seen a report as strongly worded as this. It is clear that the committee was shocked by the abuse of public money."

But, criticising a "nonsense paper chase", Ms Taylor said she was being punished for trying to reach out to as many constituents in possible, rather than "waiting in my office for people to come to see me".

She added: "I will pay up willingly, because I admit I made a mistake, but there is no suggestion that I deliberately tried to undermine the rules."