To avoid increased penalties, they just need to not commit crimes. That shouldn't present a problem at all. They have a great deal of expertise in the practical applications of the law and thus should be really well-equipped to follow it.

What is the argument to hold them to a higher standard when they are off duty?

As a class, police officers are expected to be highly knowledgeable of the law and have been trained in both hand-to-hand combat and conflict de-escalation. Off duty police officers should know when they're doing something illegal, they should be ready to stop a volatile situation from coming to blows, and they are at an unfair advantage in a fight vis-a-vis the average civilian and should thus be slower to resort to violence.

> How does that incentivize people to be Police?

Why should we incentivize people to be "Police" where "police" implies a free license to abuse civilians? In fact, people who are deterred by an abuse license repeal are probably the right people to deter from service jobs like policing.

Your analogy is flawed. If someone is a board/director in a company they have additional scrutiny. Why would they ever take that job?

The question should be, would otherwise great people NOT join the force if such a control isn't in place?

Also, without controls - you attract exactly the wrong people (power-hungry bullies).

The question as phrased assumes that the primary incentive for joining the police is impunity for casual lawlessness. That's dystopian.

You could also ask the same question of skilled martial artists and armed forces veterans. Both classes can face higher penalties, but that doesn't deter people from becoming Army Rangers or karate black belts.

It should incentivize them to act with a high degree of professionalism and regard for the law. What’s the point of granting them extraordinary powers over life and liberty if they’re not held to a higher, not lower, standard?

People who work for a broker or market making bank are heavily scrutinized and they, their family, and to some degree associates (room mates, etc) are restricted in their basic conduct - political activity, investing, etc, and face increased penalties for financial crimes vs the average person. It’s telling we hold our money handlers to a higher standard than the armed representatives of the government with extraordinary rights to deprive people of their liberty and life. Money is more important than our freedom and safety?

On recruiting officers by making the job come with the perks of immunity for criminal behavior, seems like we should find another strategy. If you can’t identify yourself as the police before you beat someone half to death, maybe you’re not qualified to be a law enforcement officer? Maybe we should be glad they wouldn’t take the job if it came with reasonable protections for the people they’re supposed to be protecting?

Seriously, most professional careers come with obligation of avoiding even the appearance of impropriety.