The IRS sets the guidelines on who is considered an employee (receives a W-2) and a contractor (receives a 1099). Employers need to make sure they have properly classified these individuals because the government is coming down hard on violators.
It’s important to understand that a contractor is not an employee. They don’t receive benefits. They should have a contract with a specific project to complete. The work is project-based. The person should not be doing day-to-day work for the employer. They should work for multiple organizations and show their own profit and loss and have their own insurance.
There are three factors the IRS looks at to determine whether someone is a contractor or an employee. There’s the behavioral, financial, and type of relationship. If any of these factors are not in place, then the individual is an employee and not a contractor
If you have more questions, I suggest consulting with an experienced HR professional.