Instead of lowering corporate tax rates for all companies just determine a set of criteria for a corporate good citizen status.
Companies that achieve this could eligible for lower taxes and any dividends paid to shareholders could also be tax exempt.
For example a corporate good citizen company would probably need to be a good employer and definitely not need public funds diverted to fix environment or health issues caused by their actions.
Other criteria could be decided that may include transparency, fair dealing with customers, executive remuneration, staff satisfaction and retention.