Washington employee handbooks need to contain five mandatory federal policies, as well as 10 required state policies. Washington's Best Resource on the Ever-Changing Laws Governing the Employer-Employee Relationship.Is It Mandatory to Create a Staff Handbook in the UK? The short answer is that it's not mandatory. To create a legally compliant handbook, employers should: Understand which federal employment laws apply. What should be in your employee handbook? In this article, learn the benefits of a staff handbook and which policies you should include. Employee handbooks should contain individual workplace needs in accordance with the requirements of Washington's state and federal laws. Welcome to the Washington State Bar Association! Employers must take steps to ensure their handbooks are well-drafted.