For the third time since he became prime minister in 2015, the behaviour of Justin Trudeau is being investigated by the Conflict of Interest and Ethics Commissioner. The investigation involves a proposed non-tendered contract worth $19 million to the WE Charity, which was supposed to operate a new student-volunteer program. Trudeau had participated in the cabinet meeting that approved the contract.

Because both the prime minister and his wife had a close relationship with the charity, the opposition complained to the ethics commissioner that Trudeau was guilty of violating the conflict of interest law. Days later it was revealed that Trudeau’s mother and brother had been paid nearly $300,000 for multiple speaking engagements at WE Charity events. This seems to be a classic case of confusing or intermingling private interests with the public interest, which is the essential nature of a conflict of interest.

The case caused me to reflect on why politicians appear to have such difficulty reasoning and acting ethically. Here are some random thoughts:

There is illegal and unethical behaviour in all occupations, but politics seems to involve greater temptations and risks that legal rules and ethical standards will be violated.

Politics involves contention over competing ideas and interests, together with competition to gain power, and these fundamental facts can override respect for ethical norms. Politicians and their advisers take the pragmatic view that if they do not break or bend the rules, they will lose ground to their opponents. They tell themselves that after they win, they will behave in an exemplary ethical manner, but then re-election becomes a strong motivation.

Most politicians enter public life for altruistic reasons of public service. A minority, however, become corrupted by the political process. They develop the view that politics is a game and to the winner go the spoils. Individuals from a famous political family, or long-serving politicians, may develop the view that they are, as a former Liberal cabinet minister declared, "entitled to their entitlements." Rewarding family and "political friends" is seen as a perk of the job.

Politicians face three broad types of ethical problems:

There are the ethics of their policy choices, which reflect their value systems and often have distributional impacts on who within society loses and wins as a result of those choices. These are matters for public debate and election contests.

To promote honesty and to deter favouritism, the process for deciding policy and allocating resources has been the target of ever-expanding regulation and other accountability mechanisms. The result is that politics today is "cleaner" in terms of legality and ethics than in the past.

The relatively new ethics regimes cover only actions connected to the performance of public duties. They do not cover the private behaviour of politicians. In the case of ethically problematic behaviour, such as having an affair, the penalties may come at the next election if enough voters are offended.

Often, politicians defend their transgressions by claiming their behaviour could be seen as unethical, but it was not illegal. The distinction is simplistic and false; fundamental ethical values provide the foundation for law. Over time, many behaviours deemed ethically questionable have become prohibited or regulated by laws. This contributes to the incorrect public impression that contemporary politicians are more corrupt than their predecessors of bygone generations.

With the adoption of conflict of interest, access to information and whistleblowing laws, there are more disclosures of alleged wrongdoing by politicians. In the negative and theatrical cultures of legislatures, the opposition parties tend to exaggerate the seriousness of the misdeeds involved. Opposition accusations are then amplified and sensationalized in the traditional and the new social media. The result is the emergence of a political culture that is increasingly driven by scandals rather than by reasoned policy debates.

The public believes all politicians should know the difference between right and wrong and act accordingly. In political life it is not that simple, because there are numerous competing values and ethical dilemmas. Not every individual who enters political life is capable of ethical understanding, reasoning and judgment. The pressures and demands of the job mean there will always be ethical lapses.

We have probably reached the limits of using stricter laws, supported by tougher enforcement, to curb illegal and unethical political behaviour. Rather than focus mainly on preventing and punishing wrongdoing, more effort needs to be placed on promoting "right-doing." A code of ethical conduct for political parties, candidates, elected representatives, paid staff and volunteers would help, but only if it was backed up with meaningful educational and enforcement activities.

The code would be particularly useful in encouraging ethical awareness in those "grey zones" where values clash and the difference between right and wrong is blurred.

Paul G. Thomas is professor emeritus of political studies at the University of Manitoba. In 2014 he wrote a report for Elections Canada on a code of ethics for political parties.