The Independent Television Commission issued a 'formal warning' to the network, saying the use of a knife, particularly one as accessible as a kitchen knife, as the murder weapon breached its programme code.
The warning - the first under a new system introduced this year - is specifically about the 8 May omnibus edition which went out at 5.05pm on a Saturday, regarded as family viewing time. The soap, which is shown three times weekly, had first shown the scene at 8pm the previous evening.
Channel 4 said its board had unanimously endorsed the showing of the episode. Its chairman, Sir Michael Bishop, said the warning raised 'serious editorial issues of principle' and would be considered by his board on Monday.
Phil Redmond, the series' creator and executive producer, said: 'It's the role of Brookside to stimulate discussion and debate. I am glad to say that we are doing that.
'No matter what the regulator says, the overwhelming response from the audience and professionals has been supportive.'