An alcoholic police chief was forced to resign after she was caught drink driving - almost four times over the limit, a court heard.

Acting Superintendent Elizabeth Byron, head of Hertfordshire police's traffic department, was stopped by officers while on sick leave after she crumbled under the pressure of her work.

Magistrates in Bishop Auckland, Co Durham, heard how the high flying 43-year-old cop had buckled under the ever growing strain of her job, which had forced her to work between 70 and 92 hours a week.

Her health declined, she took sick leave and now attends Alcoholics Anonymous sessions five days a week. She also attends a rehabilitation clinic.

The court was told how Ms Byron joined the Hertfordshire force aged 18 in 1978.

She rose through the ranks from a lowly PC top become a sergeant in 1986, inspector in 1993, chief inspector five years later and acting superintendent in 2001.

The magistrates were told how she fell ill in November last year and was prescribed medication to combat her stress and depression.

On May 29 this year, while still on sick leave, she was spotted by a police patrol car on the A66 at Lamb Hill, near Barnard Castle, Co Durham, driving her Y reg Nissan Almera erratically.

She was pulled over and gave a roadside breath test followed by two further tests at a police station.

The court was told she recorded 127 microgrammes of alcohol in 100 milliletres of breath, the legal limit being 35.

Today Ms Byron, of St Albans Road East, Hatfield, Herts, admitted one charge of drink driving, contrary to the road traffic act 1988.

Magistrates were told it was her first appearance before a court and she had one other offence for speeding in 2000 for which she received three penalty points.

Lynn Simpson, mitigating, said that with "added responsibility came added pressure" for the senior officer.

She said that since she was stopped for drink driving by police she realised her illustrious 25 year career was now in ruins and she had notified the Chief Constable of Hertfordshire of her resignation.

Mrs Simpson said: "My client now suffers with clinical depression. She had been working between 70 and 92 hours each week.

"By this time last year she was on high doses of medication and she deeply regrets what has happened as the consequences have been absolutely horrific for her."

She said the former police chief would now lose her police-owned home, salary and she was "struggling to make ends meet" and had sought advice from financial experts at the Citizens' Advice Bureau.

She said: "Ms Byron has taken a number of steps to tackle the problems she has and has had substantial help from the police federation.

"She currently attends AA five times a week and attends rehabilitation.

"She is obviously taking steps to help herself and she recognises the problems she has."

Chairman of the magistrates, Sue Snowdon, said: "We realise you have taken steps to address your problems and this goes in your favour.

"Unfortunately the drink drive reading you gave was excessively high and because of that we are requesting that a full pre-sentence report is carried out so we can further address the problems that you have."

Sentencing of the officer was adjourned until September 10 and she was issued with an interim driving ban until that date. Byron, who wore a beige suit, was visibly shaking throughout the hearing and at one stage in the proceedings broke down in tears.

She was handed a tissue and a glass of water by a court usher as she attempted to compose herself.

She left court again on the brink of tears and refused to comment as she was driven away by her solicitor.

As part of her remit Byron was head of the Strategic Road Policing Unit which meant she was head of the traffic department. Part of her responsibilities were heading the fight against drink drivers and speeding motorists.