Mr Clarke will be speaking on Wednesday to the annual conference of the Police Federation, whose members believe that they are being unfairly treated by proposals to create a system based on civilian personnel management procedures.
Despite a welcome by the police for last week's retreat on the Criminal Justice Act, the service is apprehensive. Reeling from criticisms over miscarriages of justice and inefficiency it is now facing a shake-up in police authorities and an inquiry into pay and responsibilities; there is also anger with Mr Clarke over his refusal to allow trials of the long side-handled baton.
Alan Eastwood, the outgoing chairman of the federation, said: 'The discipline paper is the final straw and is expected to dominate discussions at this conference. The police service are on the Government's hit list and we feel we are being treated abominably.'
Although Mr Eastwood emphasised that Mr Clarke will be received courteously, some fear a repetition of last autumn's meeting of the Metropolitan branch of the federation when Mr Clarke was booed and heckled.
Mr Eastwood has written to the Prime Minister objecting to the proposals, which include the abolition of the 'beyond reasonable doubt' standard of proof and an end to automatic legal representation and an officer's right to silence in many cases. Chief officers will have the power of instant dismissal.
The conference is expected to endorse overwhelmingly a motion committing the federation to pressing for the police to be allowed full trade union rights if the proposals are implemented, which could lead to officers seeking the right to strike. Formal recognition of a police officer's status as an employee, rather than as a servant of the Crown, would make them liable to health and safety legislation.
Mr Clarke stunned last year's federation conference by announcing the inquiry into police pay and responsibilities. That inquiry, chaired by Sir Patrick Sheehy, is due to report at the end of June and is expected to recommend the abolition of a number of ranks and the introduction of fixed contracts and performance-related pay.
Mr Clarke, aware of the pressures on the Government, is likely to strike a balance between pressing ahead with the reforms and totally alienating the police service and it is believed that his speech could be strong on law and order as well as offering the federation some concessions.
Leading article, page 17