The Nov. 19 arrest of Nissan chairman Carlos Ghosn for misreporting his income, and the investigation into his use of company funds for homes and other perks, seem to paint a picture of gross impropriety that is uncommon in the modern corporate world.

Nonetheless, there are basic lessons that every company, public or private, should take into account in the wake of the Ghosn scandal in order to be proactive and fully transparent.

The importance of setting a tone of zero tolerance at the very top can’t be overstated. Boards must ensure proper segregation of duties in the context of executive compensation reporting, no matter the context (regulatory filings, board presentations, investor communications, etc.). In other words, there should be effective firewalls between the payroll and reporting functions.

Boards also should establish, and independent auditors should perform, “agreed-upon procedures”in order to provide additional assurance, beyond that associated with a standard audit, that disclosures are complete and the numbers are correct.

To avoid any suspicion of misappropriated assets, C-suite executives should provide annual representations that they have read and complied with these policies and practices, with spending subject to independent review.

For example, if an apartment or private jet is available for executives, the auditor could perform audit-like procedures to verify that all executive use was in the interest of the company in accordance with its established policies.

It’s also important to regularly review both the master list of vendors and actual payments to them in order to ensure that an executive doesn’t authorize a payment to, for example, a vendor he or she controls, a relative, etc.

More Is Better

When it comes to executive compensation, which is certainly a hot-button topic in the United States, over-disclosure can be a good thing. A full picture of compensation, including all perks and deferred compensation, even if they seem standard, should be reported to avoid the implication of anything clandestine.

Deferred compensation, a central aspect of the case against Ghosn, can be tricky, since the amount reported must be the current estimate of expected payments, and not guaranteed payments. The final amount paid will depend on market factors that will continually unfold until the executive retires.

However, a good-faith estimate of the current value of that compensation could, and probably should, be reported each year. Nissan’s example demonstrates why that’s a good idea.

Compliance lapses such as those that occurred at Nissan are much more likely if there’s a rubber-stamp audit committee — which, in turn, is enabled when company management takes the committee’s oversight role lightly or views it as burdensome.

Although establishing the additional “agreed-upon procedures” is not required by law for U.S. companies, the board of any particular company could regard their use as a standard mini-audit in a variety of situations. With respect to executive pay, the practice could provide much-needed credibility that the compensation plan is adhered to in practice, not just on paper.

If Nissan is to regain the trust of regulators and investors, it is vitally important that the company institutes extra procedures beyond what’s required by the letter of the law. That’s why the reporting of these additional measures are sometimes called “comfort letters.”

Nissan’s auditor, Ernst & Young ShinNihon, reportedly raised questions about the company’s interpretation of corporate disclosure rules and reacted appropriately. This shows the value of having an outside firm, selected on a periodic or rotating basis, look at the company’s C-suite expenses and uses of company assets, checking for anomalies, incomplete information, or potential disclosure issues.

For example, when scrutinizing the corporate jet log, the auditor can make sure that all hours were truly spent on company business, and that an executive didn’t divert for a vacation or family wedding.

And again, vendors should be a key area of concern. None should have a personal connection to executives who select and pay them. Keep a master list of vendors, ensure they are vetted, and establish periodic attestations against conflicts of interest.

These recommendations are onerous and go beyond minimum requirements. But there is no such thing as too much disclosure and transparency when working to avoid the kind of reputational and accountability issues that Nissan now faces.

Robert Rostan is CFO of Training The Street, a financial-education firm.