The Supreme Court looked at employer’s liability at common law from the Scottish perspective.  Lord Reed and Lord Hodge said,

Common law liability
107. It may be helpful at the outset to address a general point arising from the opinions of the Extra Division. They contain numerous comments to the effect that it is unreasonable to suggest that [the Claimant’s] employer should have provided her with special footwear designed to reduce the risk of her slipping and falling, since she was in the same position as any other member of the public travelling on foot in wintry conditions. It was in that context that the Extra Division stressed the “necessary basic questions” identified by Lord President Dunedin in Morton v William Dixon Ltd, and referred to the Caparo test: see para 32 above.

108. One can understand the Extra Division’s concern that the law should not be excessively paternalistic.

[The Claimant] was not, however, in the same position as an ordinary member of the public going about her own affairs. It was her duty, as someone employed by [the Defendant] as a home carer, to visit clients in their homes in different parts of the city on a freezing winter’s evening despite the hazardous conditions underfoot.

Unlike an ordinary member of the public, she could not choose to stay indoors and avoid the risk of slipping and falling on the snow and ice.

Unlike an ordinary member of the public, she could not choose where or when she went. She could not keep to roads and pavements which had been cleared or treated.

She could not decide to avoid the untreated footpath leading to [the] door.

Unlike an ordinary member of the public, she was obliged to act in accordance with the instructions given to her by her employers: employers who were able, and indeed obliged under statute, to consider the risks to her safety while she was at work and the means by which those risks might be reduced.

In those circumstances, to base one’s view of the common law on the premise that [the Claimant]was in all relevant respects in the same position as an ordinary member of the public is a mistake.

109. Furthermore, the common law relating to employers’ liability was not definitively stated by Lord Dunedin in Morton v William Dixon Ltd.

As long ago as 1959, Lord Keith of Avonholm devoted his speech in Cavanagh v Ulster Weaving Co Ltd [1960] AC 145 to the clarification of Lord Dunedin’s dictum.

He observed that the ruling principle was that an employer was bound to take reasonable care for the safety of his workmen, and all other rules or formulas must be taken subject to that principle (a point which had earlier been made, in relation to Lord Dunedin’s dictum, by Lord Normand in Paris v Stepney Borough Council [1951] AC 367, 382 and by Lord Reid in Morris v West Hartlepool Steam Navigation Co Ltd [1956] AC 552, 571, amongst others).

He added that Lord Dunedin could not have intended to depart from or modify that fundamental principle. Both in that case and in Brown v Rolls Royce Ltd 1960 SC (HL) 22; [1960] 1 WLR 210 Lord Keith emphasised that Lord Dunedin was laying down no proposition of law.

110. The context in which the common law of employer’s liability has to be applied has changed since 1909, when Morton v William Dixon Ltd was decided.

As Smith LJ observed in Threlfall v Kingston-upon-Hull City Council [2010] EWCA Civ 1147; [2011] ICR 209, para 35 (quoted by the Lord Ordinary in the present case), in more recent times it has become generally recognised that a reasonably prudent employer will conduct a risk assessment in connection with its operations so that it can take suitable precautions to avoid injury to its employees.

In many circumstances, as in those of the present case, a statutory duty to conduct such an assessment has been imposed.

The requirement to carry out such an assessment, whether statutory or not, forms the context in which the employer has to take precautions in the exercise of reasonable care for the safety of its employees.

That is because the whole point of a risk assessment is to identify whether the particular operation gives rise to any risk to safety and, if so, what is the extent of that risk, and what can and should be done to minimise or eradicate the risk.

The duty to carry out such an assessment is therefore, as Lord Walker of Gestingthorpe said in Fytche v Wincanton Logistics plc [2004] UKHL 31; [2004] ICR 975, para 49, logically anterior to determining what precautions a reasonable employer would have taken in order to fulfil his common law duty of care.

111. It follows that the employer’s duty is no longer confined to taking such precautions as are commonly taken or, as Lord Dunedin put it, such other precautions as are so obviously wanted that it would be folly in anyone to neglect to provide them. A negligent omission can result from a failure to seek out knowledge of risks which are not in themselves obvious. A less outdated formulation of the employer’s common law duty of care can be found in Baker v Quantum Clothing Group Ltd [2011] UKSC 17; [2011] 1 WLR 1003, para 9.

112. In the present case, [The Defendant was] were aware of a history of accidents each year due to their home carers slipping on snow and ice, and they were aware that the consequences of such accidents were potentially serious. Quite apart from the duty to carry out a risk assessment, those circumstances were themselves sufficient to lead an employer taking reasonable care for the safety of its employees to inquire into possible means of reducing that risk.

113. Had such inquiries been made, or a proper risk assessment carried out, the implication of the evidence accepted by the Lord Ordinary is that [the Defendant] would have learned that attachments were available, at a modest cost, which had been found to be effective in reducing the risk, and had been provided by a number of other employers to employees in a similar position. In those circumstances, the Lord Ordinary was entitled to conclude that [the Defendant was] negligent in failing to provide [the Claimant] with such attachments.

114. It is necessary only to add that the familiar threefold test set out by Lord Bridge of Harwich in Caparo is not relevant in this context, as counsel for Cordia acknowledged. That test is concerned with the imposition of a duty of care in novel circumstances. There is no doubt that an employer owes a duty of care towards its employees. The question in the present case is not whether a duty of care existed, but whether it was fulfilled.

Emphasis added. Edited for ease of reading.