Former Post Office bosses could be hauled to give evidence to an inquiry after it was promised new powers yesterday. The probe into the postmasters scandal is to be upgraded to a ‘statutory’ footing, meaning witnesses face imprisonment if they fail to appear. It could mean Post Office chiefs who presided over the UK’s biggest miscarriage of justice finally being compelled to take the witness stand. Innocent postmasters, often the pillars of their village communities, were sacked, jailed or made bankrupt over mysterious shortfalls in their branch accounts – when in fact a computer glitch in the Horizon IT system was to blame.