Written counseling is important. I have advised and represented small business owners. The best protection from a false claim is written counseling made at the time of the alleged infraction. Even the most basic workplace will have scratch paper somewhere. You as a manager need to include the basics: what the employee did wrong, when s/he did it, and what you as the manager expect in the future. This written documentation will help tremendously when/if the employee later seeks unemployment benefits or files suit for alleged discrimination.