Desperate mum wants cannabis to be legalised to stop her son from going blind

A desperate mum is in a race against time for cannabis to be legalised - because it can stop her son from going blind.

Sam Clark, 14, was diagnosed with retinitis pigmentosa (RP) at just four years old, a rare genetic disorder which leads to blindness through gradual vision loss.

Registered blind, the teenager can only see in the daylight and has severe tunnel vision which he compares to looking through two dark, thin straws.