Emma Shaw died at the West Bromwich flat she shared with her partner.

The 22-year-old was dealing with a leak from a boiler at her Jefferson Place flat in Grafton Road when tragedy struck in December 2007.

Prosecutors had alleged a form showed all of the electrical circuits had been signed off as 'problem-free' and a final signature was given by Neil Hoult, a qualified supervisor.

Investigations later revealed a circuit which fed an immersion heater in the boiler had been penetrated by a screw during the flat's construction.

Hoult, aged 53, of Dane Terrace, Rowley Regis, was yesterday found guilty by jurors of one charge of failure to discharge a duty under the Health and Safety at Work Act.

The jury continues to deliberate over a similar charge faced by Mr Hoult's co-accused Christopher Tomkins, 52, of Rowley Village, Rowley Regis. Miss Shaw was found dead in a storage room by her partner Andrew Cross after he returned home from work to answer her frantic text messages about a pipe that had fallen off and saying 'the electrics were sparking'.

Her then 23-month-old son had been in the living room when she was electrocuted.

The court heard Tomkins and Hoult were employed by Anchor Building and Electrical Services Ltd, which was contracted to carry out electrical work during the development of Jefferson Place in 2006. Hoult denied the charge, and Mr Gary Bell, defending, said he had relied on the 'honesty and competence' of his fellow workers that vital tests had been carried out on the electrical cabling.

He signed off certificates saying safety checks had taken place. Hoult declined to give evidence but Mr Bell said Hoult had not been based on site as his responsibility was to check the details on forms sent in by workers before signing them off.

The court has been told Hoult's co-defendant Tomkins had filled out a form showing circuits to the flat had been 'dead tested' for insulation resistance – but he has admitted he did not do that test. Tomkins said he had been assured by his foreman that this work had already been carried out. But the court was told it had not been done as it would have uncovered the damaged circuit.