Long v British Gas Trading Ltd - Sex discrimination and part-time worker detriment

The employment tribunal recently found that an employee who returned to work from maternity leave on a part-time basis after having triplets was subject to sex discrimination and less favourable treatment compared to a full-time equivalent male worker.


Equality Act 2010

Section 13

(1) A person (A) discriminates against another (B) if, because of a protected characteristic, A treats B less favourably that A treats or would treat others.”

Section 11

In relation to the protected characteristic of sex—

(a) a reference to a person who has a particular protected characteristic is a reference to a man or to a woman;

(b) a reference to persons who share a protected characteristic is a reference to persons of the same sex.

The Part-time Workers (Prevention of Less Favourable Treatment) Regulations 2000

Section 5

(1) A part-time worker has the right not to be treated by his employer less favourably than the employer treats a comparable full-time worker—

(a) as regards the terms of his contract; or

(b) by being subjected to any other detriment by any act, or deliberate failure to act, of his employer.


The claimant had worked as an intellectual property (IP) counsel since January 2012 and, when she returned from maternity leave in September 2017, was one of two IP lawyers, the other of which worked full-time. The claimant was paid £46,800 per year for working three days per week, 8am-4pm Monday-Wednesday. Her full-time colleague resigned in June 2018, leaving her to cover both roles for around six months before a replacement was hired. During this time, the claimant felt considerable pressure from her managers to work over and above her contractual hours, including on her non-working days.

Her performance review in 2018 contained mixed feedback, but nothing which led the employee to believe that she was performing below expectations. Despite this, she was placed on a performance improvement plan (PIP) in March 2019. At the same time, a new full-time male IP lawyer was hired on an £80,000 annual salary; his full-time equivalent wages were more than the claimant’s. British Gas were unable to show that the difference between her pay and that of the newly appointed male employee was unrelated to sex.

On 6 June 2019, she was told she was at risk of redundancy. The tribunal found the grounds for redundancy to be genuine but was dissatisfied with the selection process used. British Gas utilised a scoring matrix to decide who to make redundant. In this, the claimant scored 1 out of 7 for “focus”, which, according to the respondent’s commentary, meant she rarely demonstrates this capability and/or sometimes demonstrates the opposite.


The Employment Tribunal found the respondent’s expectation for the claimant to work outside of her contractual hours to be unsustainable and unreasonable. The ET also found that the claimant was placed at a disadvantage due to a discriminatory performance capping policy which saw her annual performance not being able to surpass “achieving expectations” as a result of her taking maternity leave. This low and disproportionate result was given even though her appraisal in 2017 highlighted that she was exceeding expectations. As such, it was decided that the policy operated in a discriminatory way against women.

Additionally, the employment judge decided the selection criterion utilised in the redundancy process (specifically, her “focus” score) to be irrational and concluded that the employee’s personal circumstances as a mother of young children was unconsciously being held against her. Further flaws in the redundancy process included a failure to take into consideration how a long-serving employee like the claimant (seven years) could be reasonably compared against the new, short-service employee (less than one year).

The employee’s claims for sex discrimination, less favourable treatment on the grounds of part-time working, unfair dismissal and equal pay were successful. Her beliefs that the company assumed she was not performing as well as a full-time male colleague and was less focused because she was a woman with triplets working three days per week, were well-founded.


There are several key takeaways from this case. Firstly, it highlights the issues which can arise when a redundancy process, and the selection criterion utilised, is unfair or unequal, even when the reasons for making a redundancy are genuine and reasonable.

In addition, the case shows the importance of treating all employees the same, regardless of their working hours and gender. Assuming an employee’s performance will struggle based on their part-time hours and family circumstances can amount to successful tribunal claims, as seen here. Therefore, employers should objectively consider output before taking action against an employee. Where action is appropriate, employers should also consider what support options may help the individual to improve and provide ample opportunity for them to do so.

Finally, the case showcases the need to pay employees equally for work of equal value. In today’s competitive job market, many employers may be tempted to say the offering of a high salary to a new starter is a necessary recruitment tactic, to ensure they are able to attract candidates. However, unless this can be justified, the tribunal may continue to find the only reason for salary differentials to be sex.

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