Argument: Politicians who commit crimes are likely unfit to serve.

The sort of person who commits an offense has demonstrated irresponsibility and so is unworthy of the public trust. Would any reasonable citizen wanted to be represented by a domestic abuser, or have a fraudster manage the public treasury? While almost all people are capable of atonement and redemption, someone who commits crimes worthy of prosecution while in office ought to be immediately removed for the betterment of the state.

Candidate 1: "The concept of retribution is a narrow and dubious foundation for justice. A modern, civilized legal system should not be geared around delivering payback on behalf of victims, but rather around advancing the best consequences for the future. For exactly this reason legal systems give several ways in which defendants can avoid punishment, even though they are technically guilty, if punishing them would have bad consequences; these include jury nullification and suspended sentences."
Candidate 2: "This is not necessarily true. A politician could be a brilliant diplomat who happens to commit a minor offence such as drink driving; very few indictable offences correlate directly with one’s ability to discharge the mandate of a political office. Historically, politicians have often had their secret vices, including the rumored drug habits of many 19th century politicians, that have not impeded the performance of their duties."
Candidate 3: "No one doubts that politicians have to make morally difficult decisions, where sometimes every option is unpleasant. However, no one wants politicians to have an unrestricted ability to make ethical questionable decisions. That is exactly what immunity would deliver them. A politician who knows that they cannot be touched is incentivized and licensed to be much more brazen in their behavior when in office, and we want a bulwark against unrestricted rule-breaking. A state of affairs wherein politicians can sometimes be prosecuted creates the ideal amount of disincentive for politicians to break rules; they will do so only when there is a pressing need, and only to a moderate degree. Because of the plausible justifications for such acts, politicians need not fear prosecution in the overwhelming majority of cases. For instance, no official from either the UK or USA has been actually indicted with regard to highly-legally-dubious programs to torture detainees [1] [2] . Moreover, politicians are seldom prosecuted anyway, especially because they tend to belong to socioeconomic strata that punished less or not all compared to the rest of society. There is no legitimate need to give them more protection.

[1] Ambinder, Marc, ‘CIA Officers Granted Immunity from Torture Prosecution’, The Atlantic, 16 April 2009, http://www.theatlantic.com/politics/archive/2009/04/cia-officers-granted-immunity-from-torture-prosecution-update/16268/ [Accessed September 9, 2011]

[2] Human Rights Education Association, ‘Torture, Inhuman or Degrading Treatment’, hrea.org, http://www.hrea.org/index.php?doc_id=265 [Accessed September 9, 2011]"
Candidate 4: "These mechanisms are not immediate enough to put an immediate stop to an aberrant behavior. Impeachment proceedings take months at least; elections may be years away; and reputational damage is even more long-term. Moreover, these punishments are nowhere near a sufficient deterrent. If loss of one’s job, and damage to one’s public image were sufficient deterrents, we would not prosecute business leaders for insider trading, nor celebrities for drunk driving. The fact is that a criminal justice system which punishes everyone equally is not just fair; it’s also a practical method of achieving meaningful deterrence. Finally, even if we are willing to settle for one of these lesser punishments, the threat of a great punishment gives prosecutors leverage to strike deals with the politicians, such as offering not to prosecute in exchange for coming forward with the details of misdeeds."
Candidate 5: "The difference between the harm to the office of a politician getting away with a crime and the harm from them being tried for that crime is that the trial is inherently public. Short of widespread corruption – the sort that would probably preclude prosecuting politicians anyway – it is unlikely that unpunished wrongdoing in an office will ever become public. A trial, by contrast, creates a media flashpoint that captures the public consciousness. Thus, even if the damage to the integrity of the office is greater per person in cases of unpunished crimes, the act of punishing the crime informs enough people to outweigh the fact that it may not do as much damage per capita."
Candidate 6: "If we don’t want politicians hurting the dignity of the office, there is only one thing we can do: not elect politicians likely to commit crimes! Of course, this is often impossible to tell in advance, but the dilemma remains: a crime has been committed, and that hurts the dignity of the office no matter what action we take. One thing that’s worse than having an office’s holder raked over the coals is for them to get away with a behavior that otherwise warrants punishment. See discussion below under “hurts the image of the office.”"
Candidate 7: "See argument above regarding other accountability mechanism. Jeopardizing future electoral success, harming one’s political party, and damage to one’s personal legacy are all meaningful checks on the behavior of politicians. To suggest that, in the absence of prosecutions, an under-used tool anyway, politicians will be able to abuse their station with impunity, is simply untrue."
Candidate 8: "Politicians have to divide their focus anyway. As the examples above concede, being a politician means being pulled in several different directions. Elections are particularly distracting, and in jurisdictions with fixed election cycles like the United States can make periods of up to a year prior to the election a write-off for getting real work done. Thus, personal liability is nothing special among the many concerns a politician has. In fact, accountability, of this direct type, and for serious offences, is probably more important than most of the things a politician is forced to consider, and at the very least deserves inclusion among them."
Candidate 9: "Motivation does not matter. Almost every time someone presses criminal charges, it is for their own personal concerns (such as wanting retribution), rather than concern for the public good; that does not change the fact that if charges are laid, it is because the prosecuting authority has decided that, regardless of why the crime has come to their attention, the interest of society at large requires that the individual be prosecuted. If political motivations are what is needed for politicians to be held accountable, so be it. Even if this is a problem, it can be mitigated with sufficient oversight from an independent prosecuting authority."
Candidate 10: "With regard to this issue, elections are unquestionably an effective alternative mechanism. The act of a politician in a liberal democracy holding on to office for another term, by definition, requires public assent. The citizenry has an out: don’t continue electing politicians who aren’t serving the public interest. Regardless, politicians already have a plethora of motives, both legitimate and self-serving, to hold on to public office; this doesn’t move the barometer on incentives to run. Most elections are at least modestly well contested precisely because many qualified candidates really want the position."

This is not necessarily true. A politician could be a brilliant diplomat who happens to commit a minor offence such as drink driving; very few indictable offences correlate directly with one’s ability to discharge the mandate of a political office. Historically, politicians have often had their secret vices, including the rumored drug habits of many 19th century politicians, that have not impeded the performance of their duties.
