Police officers who commit serious misconduct should have their pensions docked, a group of MPs has said.
The Home Affairs Select Committee also called for a new code of ethics for all officers in England and Wales.
Its report comes after the "plebgate" affair and a series of allegations about the conduct of undercover police.
The Police Federation said integrity in policing was "paramount", but it was yet to be convinced a new code of ethics would make a difference.
The committee said there were currently at least eight investigations under way as a result of police failings, which had so far cost £23m.
And last week, it was alleged that undercover Metropolitan Police officers attempted to smear the family of Stephen Lawrence in the wake of his murder.
The MPs recommended that the recently-formed professional standards body, the College of Policing, should "establish a scale of fines which should be docked from officers' pensions in cases of the most grave misconduct".
One officer told the committee that colleagues tempted to commit wrongdoing often weighed up what they stood to lose and their pension was seen as a big financial incentive to "keep your nose clean".
But the committee said it had learned of numerous cases where police officers facing corruption allegations had retired to avoid disciplinary proceedings and had suffered no financial penalty.
It cited the example of Sir Norman Bettison, former chief constable of West Yorkshire, who stepped down while facing a disciplinary investigation for gross misconduct charges relating to the Hillsborough disaster.
The report said there was currently no way to prevent such resignations, although the government is planning to change the system so that all disciplinary hearings will be taken to their conclusions even if the officer in question resigns or retires.
The committee also recommended that the College of Policing introduce a new code of ethics, and require all new officers to obtain a Certificate in Knowledge of Policing.
Labour MP and committee chairman Keith Vaz said the code should be like that in place for doctors.
"There are a minority of officers involved in inappropriate activities - corruption, incompetence... We need a code of ethics, integrity, and we need to make sure that there are sufficient sanctions for those who breach that code.
"Basically we want it to be like the Hippocratic oath for doctors, where there is an unshakable faith in the honesty, integrity and transparency of our police force."
He added: "The era of Dixon of Dock Green is totally over. We have new 21st Century challenges for our police service and what the public expect - as we've seen with the Stephen Lawrence case and the latest revelations about undercover agents - is the highest level of probity."
A Home Office spokeswoman said the government had already announced "a package of integrity measures to tackle misconduct and promote transparency and a more open culture in the police".
"Under these measures, the College of Policing will publish a new code of ethics and create a single set of professional standards."
From April this year, all regular recruits to the Met Police are required to achieve the Certificate of Knowledge of Policing, which covers skills like dealing with victims and witnesses, and arresting and interviewing suspects.
College of Policing chief executive Chief Constable Alex Marshall said it was working with forces to encourage a wider roll-out of that requirement.
A spokeswoman for the Police Federation of England and Wales, which represents rank-and-file officers, said it remained to be convinced "that creating a new code of ethics would be any more effective than that which already exists and one that we believe already demands the highest standards of each and every police officer".
"Further, there will be considerable cost in creating yet another discipline body within the College of Policing, along with forces themselves, the IPCC and the HMIC."
She added: "Integrity in policing is paramount, but knee-jerk reactions to historic cases and those involving an extremely small minority of the 134,000 officers who police this country with absolute commitment should not dictate future policy making."
The MPs' report also recommends that all forces publish details of misconduct hearings and their outcomes on their websites - a practice recently introduced by Scotland Yard.
And it calls for Home Office plans for a chief constables' register of interests - and a register of dismissed officers - to be implemented immediately.
Among the eight ongoing investigations currently being held into alleged police failings are Operation Alice - concerning the plebgate affair involving former minister Andrew Mitchell - and Operation Elveden, into alleged corrupt payments between police officers and journalists.