As Employers Liability is a legal requirement you will need to be sure if you do or do not need Employers Liability. You can be classed as employing people who are self-employed, sub-contractors or even volunteers.
You are likely to need to arrange EL Cover if any of the following are true:
1. You deduct national insurance and income tax from the money you pay a worker
2. You have the right to control where they work and how they do it
3. You supply their work materials and equipment
4. You have the right to any profit your workers make, even if you choose to share it with them through commission, profit share etc.
5. You require that person specifically to provide the service and they cannot employ a substitute if they are unable to work
6. They are treated in the same way as other employees e.g. they do the same work under the same conditions as someone else you employ
Further details can be found at https://www.gov.uk/employers-liability-insurance