The relevant point about subcontractors is that you subcontract to them. Therefore in classic tort theory a hirer is not ipso facto liable for the negligence of his subcontractor, although he is liable in negligence if the choice of subcontractor was negligent. Vicarious liability only arises if the negligent worker is an employee acting in the course of his employment.

Example 1. You engage a chimney sweep to sweep your chimney in your semi-detached house. He ses the chimney is badly sooted and decides to do a draught test with lighted paper. The lighted paper goes up the chimney (showing good draught) but sets light to a deposit of soot which burns both your house and your neighbour's house down. Assuming that doing the draught test before sweeping was itself negligent, the sweep is liable to you and to your neighbour for his negligence, but you are not liable to your neighbour in negligence unless engaging that subcontractor was negligent.

Example 2. You employ an employee to deliver a lorryload of stuff. It is your lorry. He takes the lorryload of stuff home with him overnight to make the delivery the next day. At 11pm he decides he wants a kebab and drives the lorry to the kebab shop but runs over a nun on a zebra crossing. You are not liable to the nun for his negligent driving for he was not acting in the course of his employment.

Exapmple 3. You employ an employee as before. He collects your lorry and load at 11 am and while driving by the correct route tomake the delivery he runs over another nun on a zebra crossing. You are liable for his negligence in the course of his employment.

Both Transocean and Halliburton were subcontractors. BP (widely and correctly referred to in reports as "London-based BP") is quite correct to seek to place blame for their failures on them. Barack Obama as a lawyer should appreciate that, and his criticisms of "a "ridiculous spectacle" of publicly trading blame over the accident" are out of place and must I think be an attempt to play to the gallery of prejudice against "foreign corporations".

Try to keep up at the back (that means you Goosey - you seem pretty ignorant).

My original thread title still seems pretty accurate to me.