Iougle who has read the judgment and says control is at the heart if right. That has always been the HMRC test for self employment and someone else above says quite rightly that for other areas of law such as workers' rights the test can be different. We must not forget that. Tax test different from worker test. What a mess English law is (thankfully as I am a lawyer and paid to help people decide where they stand in the mess every day)......
So going with control on my cleaner example if the person contracts directly with each client and can change their hours, pay their own expenses, decide when to come then I am pretty sure they are self employed and they pay their own tax to HMRC> My cleaner is self employed. She comes and goes when she likes, the days and hours change, she doesn't come in the summer etc etc. If I had a nanny here even just part time on a regular basis and she could not send a substitute and I controller her she would rightly be employed.
Then take me... lawyer, self employed. No one is going to say that I am an employee for tax purposes most of my work. It comes in. I do it. I get no sick pay, holiday pay etc etc. It comes in from loads of different companies. I could hire someojne else to do it for me. Sometimes I'm told when it must be done for (control by the client) but not enough control to move me from self employed to employed - same with some kinds of cleaners and child minders, gardeners etc. I had a company in in the summer to cut the hedges for 3 days. They were not my employees.
I suspect the gardeners who come every week to do neighbours are not employees for tax purpose either. However if you have one person just doing your gardening all the time or even regularly 3 mornings a week and you control them eg you are Longleat those gardeners are highly like to be employed.
It has always been a very difficult test to apply and remains so. It is hard to know how we can change it however as there are so many different types of self employment services and ways of operating.