Most building contracts already contain an obligation to comply with all "statutory requirements", as the JCT puts it. That includes the CDM Regulations. Employers are not rushing to use that provision to sue the contractor, though. Why not? Probably because a breach of the CDM rules does not cause the employer any loss. It is the contractor's own employees, or those of the subcontractors, who are most at risk – and they already have rights under the Health and Safety at Work Act 1974 if they are injured.
The HSE has a vested interested in health and safety that employers often do not have. It is therefore best placed to bring prosecutions under the CDM Regulations.
Gillian Birkby, partner, Mayer, Brown, Rowe & Maw, via email.