By Nicholas Watt, chief political correspondent From The Guardian UK

Relations in coalition deteriorate as Lib Dem MP says working with home secretary has been like ‘walking through mud’

Coalition relations hit a new low on Monday night when the Liberal Democrat Norman Baker resigned as a Home Office minister after likening his experience working under Theresa May to “walking through mud”.

In a sign of the loveless nature of the coalition in the final six months before the general election, Baker announced his resignation in an interview with the Independent apparently without notifying the home secretary.

Nick Clegg, who will on Tuesday announce a replacement for Baker as minister for crime prevention with responsibility for drugs policy, alerted Downing Street earlier in the day.

Baker announced he had decided to stand down after a row over drugs policy with the home secretary showed there was little support for “rational evidence-based policy” in the Home Office. He had criticised May for sitting for three months on an official report which showed that tougher enforcement of drug laws does not lead to lower levels of drug use.

Lib Dem sources said the row over drugs policy was the final straw for Baker who had indicated to Clegg in August that he would like to stand down to concentrate on the general election fight in his Lewes constituency and on his musical career as the main lyricist and singer with the band the Reform Club.

Baker, who likened his position as a Lib Dem Home Office minister to that of a hippy at an Iron Maiden concert, told the Independent of May and her advisers: “They have looked upon it as a Conservative department in a Conservative government, whereas in my view it’s a coalition department in a coalition government. That mindset has framed things, which means I have had to work very much harder to get things done even where they are what the home secretary agrees with and where it has been helpful for the government and the department. There comes a point when you don’t want to carry on walking through mud and you want to release yourself from that.”

Clegg went out of his way to praise Baker who replaced the centre right Jeremy Browne as the Lib Dem Home Office minister last year in a bid by the deputy prime minister to give a harder edge to the coalition. Baker’s resignation – and Clegg’s support after a strongly worded attack on the home secretary’s style of management – shows how coalition relations will become frayed in the countdown to the general election in May.

Baker said he was pleased to have spearheaded initiatives on female genital mutilation, antisocial behaviour and animal experiments. But he highlighted his frustration at the Home Office which contrasted, he said, with his time as a transport minister.

He said: “I regret that in the Home Office, the goodwill to work collegiately to take forward rational evidence-based policy has been in somewhat short supply.”

In the traditional letter of reply, Clegg expressed strong sympathy for Baker and said he hoped he would return to ministerial office after the election if the Lib Dems form another coalition government.

The deputy prime minister wrote: “Thank you for the brilliant job you have done … You have proved yourself as one of the most effective ministers in government: always determined to deliver a more liberal agenda for Britain, by consensus where possible but by confronting vested interests whenever necessary.”

Baker’s decision to resign with a strong parting shot at one of the most senior Tories in the cabinet will raise questions about the Lib Dems’ commitment to the coalition. But senior Lib Dem sources are adamant that the coalition will remain in place until the election because Clegg believes that one of the Lib Dems’ main arguments at the general election – that the party acted in the national interest by entering government at a time of fiscal crisis – is best illustrated by remaining in office for the full allotted five years.

But the deputy prime minister is keen to highlight differences with the Tories as part of the Lib Dems’ differentiation strategy.

Baker’s clashes with May over drugs policy prompted him last week to accuse the home secretary of having suppressed the government’s first evidence-based survey of international drugs laws.

The report said there was no evidence that tough enforcement of laws on personal possession has led to lower levels of drug use.

Baker hit back at the Tory response to the report which resulted in some sources accusing the Lib Dems of being soft on drugs. He told the Independent: “The phrase ‘soft on drugs’ is used. What is soft on drugs? I think being soft on drugs is pretending there isn’t a problem, and this is being sorted. If anyone is soft on drugs it’s my Conservative colleagues, because they are the ones who allow the process to go on whereby drug dealers continue to make money and people continue to get fined and carry on taking drugs.”

The former minister praised May for her professionalism but said that she had never accepted him after he was appointed to the Home Office without any consultation with the home secretary.

Baker said: “To be fair to the home secretary, I think she takes the view she has to keep a tight leash on everything otherwise she wouldn’t carry on as home secretary – she has been there four-and-a-half years. I think she is quite competent and professional, and I have a lot of respect for her professionally. I just think it’s a pity that she took the mindset that the Lib Dems had to be put up with, and we were almost a cuckoo in the nest rather than part of government.”

IMAGE: Liberal Democrat MP Norman Baker, who has resigned as a Home Office minister. Photograph: Gareth Fuller/PA

For more on this story go to: http://www.theguardian.com/politics/2014/nov/03/norman-baker-resigns-home-office-minister?CMP=EMCNEWEML6619I2

EDITOR NOTE: Baker announced he had decided to stand down after a row over drugs policy with the home secretary showed there was little support for “rational evidence-based policy” in the Home Office. He had criticised May for sitting for three months on an official report which showed that tougher enforcement of drug laws does not lead to lower levels of drug use.