Separated at birth

Oooh, James Chesterman is jolly popular this week. The Latham & Watkins banking partner has been compared with two megastars by eagle-eyed readers. Tulkinghorn would like to present both cases for your perusal.
CASE A: Chesterman is Simon Cowell of Pop Idol fame.
The prosecution case: both have dark hair; both are male; both have bushy eyebrows.
The defence case: Chesterman does not wear his trousers around his chest; he does not gratuitously insult budding young pop stars; Cowell would never say, “It's an evolution towards a combined service”, as Chesterman was quoted as saying in last week's The Lawyer.
CASE B: Chesterman is John Hannah of Sliding Doors fame.
The prosecution case: both have dark hair; both have dreamy, soulful eyes (Mrs Tulkinghorn, pull yourself together); both have a sensitive look about them.
The defence case: Chesterman does not have a Scottish accent; he has never romanced Simon Callow (to Tulkinghorn's knowledge) à la Four Weddings and a Funeral.
The jury is still out. (But Tulkinghorn's money is on Chesterman being Kevin Webster from Coronation Street.)