If a jury has retired to consider its verdict at a criminal trial, the judge may discharge the jury if the judge is satisfied—
(a) that a reasonable period (of at least 6 hours) for the jury to deliberate on the verdict has passed, taking into account the complexity and nature of the trial; and
(b) after examination on oath of 1 or more jurors, that the jury is not likely to reach—
(i) a unanimous verdict; or
(ii) if a majority verdict would be a sufficient verdict under section 38 (2)—a majority verdict.