Performance appraisals are meant to motivate, develop and reward – but when things go wrong, they can quickly become Exhibit A in a tribunal bundle. As hybrid working becomes the norm, many employers are discovering that old appraisal habits don’t always fit the new workplace reality. Visibility is uneven, bias is harder to spot, and consistency is more difficult to maintain.

From an employment law perspective, appraisals aren’t just about feedback, they’re evidence. When challenged, tribunals look closely at how performance concerns were raised, whether criteria were applied consistently, and whether bias (conscious or not) may have played a part. An appraisal that feels ‘unfair’ to an employee can easily form the foundation of a discrimination or unfair dismissal claim.

The question for employers is: would your appraisal process withstand tribunal scrutiny or would it crumble under cross-examination?

The legal lens: what tribunals look for

When appraisals are relied on to justify a dismissal or defend a discrimination claim, tribunals take a detailed interest in how performance was assessed and why certain conclusions were reached. The starting point is process.

Tribunals will ask:

  • Were the performance standards clear, measurable and applied consistently?
  • Was the employee given fair opportunity to respond to feedback or improve?
  • Were any personal characteristics – such as sex, race, disability or working pattern – a potential factor in the treatment received?
  • Is there documentary evidence showing a fair and objective approach?

What matters is whether the process leading to a manager’s judgment about performance was reasonable, transparent and free from bias. A well-documented, consistent appraisal process can therefore be decisive in defending a claim.

Recent tribunal trends show increasing scrutiny of subjectivity in appraisals, particularly where the criteria are vague (“poor attitude”, “not a team player”) or the assessment appears inconsistent with previous feedback. In hybrid environments, differences in visibility between office-based and remote workers can also draw attention.

Where bias creeps in

Even the most experienced managers can fall prey to unconscious bias. The move to hybrid working has only amplified the risks, as informal interactions, visibility and relationships vary widely between staff.

Common examples include:

  • Proximity bias: Favouring employees who are physically present in the office more often, because they’re more visible or familiar.
  • Recency bias: Letting the most recent event overshadow earlier performance – good or bad.
  • Affinity bias: Rating people higher because they share similar interests, backgrounds or communication styles.
  • Confirmation bias: Interpreting information in a manner to support an already-formed view of an employee’s ability.

These biases can translate into real legal risk. For instance, if women or disabled employees are more likely to work remotely and are consistently rated lower, the organisation may inadvertently create an indirect discrimination issue under s19 Equality Act 2010.

The key point is that bias doesn’t need to be deliberate to be unlawful. The perception of unfairness can be enough to damage trust and the absence of clear, objective evidence can make it difficult for an employer to defend their position later.

Hybrid work and fair evaluation

Appraising performance in a hybrid environment requires rethinking what ‘visibility’ means. Traditionally, managers formed impressions from day-to-day office interactions – who spoke up in meetings, who appeared busy, who seemed most engaged. In hybrid teams, these cues are harder to recognise.

To ensure fairness, employers should:

  • Use consistent criteria for all staff, regardless of where they work.
  • Evaluate based on outputs and results, not time spent online or physical presence.
  • Ensure regular check-ins so remote workers have equal opportunity for feedback.
  • Review performance data for patterns that might suggest bias, for example, if remote workers consistently receive lower ratings.

From a legal standpoint, differential treatment between in-office and remote workers can amount to indirect discrimination if linked to a protected characteristic (for example, women working flexibly due to childcare). Even where no discrimination claim arises, unfair processes can still undermine the reasonableness of a capability or dismissal decision.

Building legal defensibility into the appraisal process

A legally defensible appraisal process is one that can demonstrate fairness, objectivity and consistency through clear records and transparent reasoning. HR professionals can strengthen defensibility by embedding the following principles:

  1. Clear criteria

Set specific, measurable and role-related objectives. Avoid vague descriptors such as ‘positive attitude’ or ‘leadership potential’ without examples. Where possible, link objectives to business outcomes or behavioural frameworks.

  1. Consistency across managers

Inconsistent scoring between teams is a common weakness. Regular calibration sessions between managers help to ensure fairness and reduce the perception of favouritism. HR oversight is invaluable here.

  1. Appraiser training

Train managers to recognise and mitigate bias. This should include awareness of how hybrid working patterns can distort perceptions. Documenting such training also supports your defence if bias is later alleged.

  1. Contemporaneous documentation

Encourage appraisers to record factual examples, not subjective opinions. Notes made at the time carry much more weight in tribunal proceedings than reconstructed accounts months later.

Tip: Write every appraisal as if it might one day be read aloud in tribunal.

  1. Employee voice

Give employees the chance to comment on or challenge their appraisal. A signed record showing the employee’s input, even if they disagree, demonstrates procedural fairness and transparency.

  1. Follow-through

If an appraisal identifies areas for improvement, ensure a clear action plan is agreed and reviewed. A dismissal following an unimplemented action plan often appears pre-determined, undermining the employer’s case.

When things go wrong

Tribunal cases involving performance management often turn not on what was said, but on what was written down. For example, an employee dismissed for ‘poor performance’ produces years of positive appraisals and no documented concerns – the employer’s case collapses because there was no paper trail showing when or how standards had changed.

An employee working remotely alleged sex discrimination after receiving lower scores than her office-based peers. The tribunal accepted that the employer’s process had unintentionally disadvantaged those not seen day-to-day. Although the company had no discriminatory intent, its lack of consistent criteria and training for managers proved costly.

The takeaway is clear: a defensible appraisal process must not only be fair – it must look fair and be evidenced as such.

If a tribunal were to read your appraisals, would they see fairness or favouritism?