Federation representatives say some of their members are being forced to risk disciplinary action because of pay cuts of up to £7,000 a year. They say some are second-jobbing as coach drivers, chauffeurs and plumbers without the permission of their chief constables.
Dennis Lay, of the Thames Valley Police Federation, said new recruits often have to supplement a shrinking basic pay.
He explained: 'Most forces want to recruit more mature entrants, people who have seen something of outside life before joining the police service. That, I agree, is a good thing.