Sick Leave Fraud: How Can UK Employers Investigate?

Suspected sick leave fraud can leave an employer unsure how to respond. There may be concerns that an employee is working elsewhere, running a business, carrying out paid work or undertaking activities that appear inconsistent with the reason they have given for being absent.

However, suspicion alone is not enough to justify disciplinary action. An employee who is genuinely unfit for work does not necessarily have to remain at home, and being seen shopping, exercising, driving or socialising does not automatically mean they have been dishonest.

The key for employers is to investigate fairly, proportionately and with an open mind. The purpose should be to establish what has happened, rather than to gather evidence simply to support an assumption that has already been made.

At SPS Investigations, we provide corporate investigation services to businesses across London and the Home Counties. Where an employer has credible concerns about possible sickness absence fraud, we can help gather relevant evidence through lawful and proportionate investigative methods.

What Is Sick Leave Fraud?

Sick leave fraud generally refers to circumstances where an employee deliberately gives false or misleading information about their health, fitness for work or reason for absence in order to receive time off, sick pay or another benefit.

There is an important difference between an employee doing something their employer did not expect and an employee deliberately acting dishonestly.

Situations that might reasonably lead an employer to investigate include:

• An employee claiming they cannot carry out particular duties while apparently performing very similar paid work elsewhere.
• An employee receiving company sick pay while regularly working within their own business.
• Information suggesting the stated reason for an absence may have been fabricated or deliberately exaggerated.
• An employee carrying out undeclared secondary employment that may conflict with their contract or sickness absence.
• A recurring pattern of absence combined with other credible information that calls the employee’s explanation into question.

These circumstances may justify further enquiries, but none automatically proves fraud or misconduct.

How Should an Employer Start a Sick Leave Fraud Investigation?

An employer should usually begin by establishing exactly why there is concern and what needs to be investigated.

A vague suspicion that an employee is “not really ill” is not a particularly useful starting point. Instead, the employer should identify the specific inconsistency or allegation.

For example, an employer might have received information that an employee who says a shoulder injury prevents them from carrying out installation work is currently performing installation work for another company.

Defining the concern helps determine which evidence is relevant and whether further investigation is justified.

Acas guidance states that workplace investigations should establish the facts of the case, gather evidence from all sides and help determine whether there is a disciplinary case to answer.^[4]

An employer should therefore remain open to evidence that supports the employee’s explanation as well as evidence that raises concerns.

Review Existing Sickness and Employment Records

In many cases, the first useful evidence is already available within the organisation.

An employer may review relevant absence records, self-certification documents, fit notes, return-to-work discussions, previous sickness reviews, work schedules and communications relating to the current absence.

The employment contract, staff handbook and sickness policy may also be important. These documents may contain conditions relating to contractual sick pay, secondary employment, outside business interests or the requirement to notify an employer about other work.

Employees can normally self-certify their sickness during the initial period of absence and generally need a fit note where an absence lasts for more than seven consecutive days.^[3]

An unusual pattern of absence may justify a conversation or review, but it should not automatically be regarded as evidence of dishonesty. There may be medical, personal or disability-related reasons for a recurring pattern.

Compare What the Employee Has Said With the Available Evidence

A useful next step is to identify precisely what the employee has told the organisation about their condition and limitations.

If an employee says they cannot perform a certain activity, evidence showing them repeatedly performing the same or very similar activity elsewhere may be relevant.

However, employers need to distinguish between an employee’s medical condition and assumptions about what someone who is ill should or should not be doing.

A fit note concerns an individual’s fitness for work. Government guidance recognises that a person’s capabilities may vary and that altered hours, amended duties or workplace adjustments can sometimes enable someone to work despite a health condition.^[2]

The question is therefore not simply whether the employee has been active. It is whether their activity is genuinely inconsistent with the information they have provided about their absence.

Does an Employee Have to Stay at Home While Off Sick?

No. Being signed off sick does not normally mean an employee must remain inside their home throughout their absence.

An employee could legitimately go shopping, walk their dog, drive, meet friends, attend appointments or exercise while being unable to perform their normal role.

Someone with a physical injury may be able to walk short distances but be unable to undertake repetitive lifting throughout a full shift. Someone absent because of stress, anxiety or another mental health condition may be encouraged to exercise or spend time outside their home as part of their recovery.

For this reason, a photograph of an employee outside their home rarely proves sickness fraud on its own.

The activity needs to be considered alongside the employee’s actual job, what they have said they cannot do and any relevant medical context.

Can an Employee Work Somewhere Else While Signed Off Sick?

Potentially, yes.

This is one of the most important issues for employers to understand when investigating suspected sickness absence fraud.

Government guidance recognises that an employee can sometimes qualify for Statutory Sick Pay in one employment while remaining fit to work in another.^[1]

A person who cannot carry out a physically demanding job, for example, might still be capable of undertaking lighter or desk-based work.

Employers should therefore compare the nature of the two roles rather than assuming that any secondary employment proves dishonesty.

If an employee has stated that they cannot carry out heavy manual work but is found undertaking administrative work elsewhere, there may be little contradiction.

If that employee is instead repeatedly performing almost identical manual duties for another employer, the evidence may deserve much closer investigation.

Employers should also consider contractual terms. Even where the sickness absence itself is legitimate, undisclosed employment could potentially raise separate issues concerning secondary work, conflicts of interest or company policies.

How Can Publicly Available Information Help an Investigation?

Open-source research can sometimes help clarify concerns without immediately resorting to surveillance.

An employee may have publicly available professional profiles, business websites, company appointments or advertisements that suggest they are operating another business or providing services during their sickness absence.

For example, publicly accessible information might indicate that an employee is advertising appointments, promoting recent work or actively trading through a company.

This evidence still needs to be interpreted carefully. An old social media post or outdated website cannot automatically establish what the employee was doing during the period in question.

Data protection obligations also continue to apply simply because information is publicly accessible. Any collection and use of personal information should have a legitimate purpose and be necessary and proportionate to the investigation.

A professional investigation should not involve attempting to hack accounts, bypass passwords, impersonate someone to gain access to restricted material or access private communications without lawful authority.

When Might an Employer Consider Hiring a Private Investigator?

An employer may consider external investigation where there is a credible allegation that cannot reasonably be resolved through internal records and ordinary HR enquiries.

For example, there might be reliable information suggesting that an employee is regularly attending another workplace while claiming they are unable to carry out substantially similar work for their employer.

A private investigator may be able to examine publicly available information, establish patterns of activity and, where justified, conduct targeted surveillance from public places.

At SPS Investigations, we first consider what the employer is actually trying to establish. This allows an investigation to focus on relevant evidence instead of conducting unnecessarily broad enquiries into an employee’s private life.

How Can Surveillance Be Used to Investigate Sick Leave Fraud?

Surveillance can sometimes provide useful evidence, but it should not automatically be used whenever an employer doubts an employee’s sickness absence.

The Information Commissioner’s Office states that covert monitoring of workers is unlikely to be justified in most normal circumstances. It may be appropriate in exceptional situations, including where there are reasonable grounds to suspect criminal activity or gross misconduct and informing the worker would prejudice the investigation.^[6]

Where covert monitoring is justified, it should be targeted, limited and appropriately authorised. The ICO also advises organisations to assess the data protection implications, including through a data protection impact assessment where appropriate.^[6]

This means an employer should have a defined investigative purpose.

Following an employee indefinitely in the hope that something suspicious happens would be difficult to justify. A targeted investigation based on credible information about particular work, locations or dates may be easier to demonstrate as necessary and proportionate.

What Can Surveillance Evidence Show?

Surveillance can establish observable facts, but investigators should avoid making medical conclusions that the evidence cannot support.

For example, an investigator might document an employee arriving at commercial premises in the morning, remaining there for several hours, carrying equipment, travelling to different addresses and appearing to undertake work-related activity.

Those observations could be relevant where the employee is suspected of working elsewhere.

However, surveillance cannot usually establish exactly what an employee is doing inside private premises, diagnose their medical condition or independently determine whether they are medically fit for their contracted role.

Individual observations also need context.

A short video showing someone lifting a box does not necessarily mean that person is capable of repetitive manual handling for an eight-hour working day.

How Should Employers Handle Medical Information?

Sickness investigations frequently involve health information, which requires particular care under UK data protection law.

Information about a person’s physical or mental health is special category personal data. Employers need an appropriate lawful basis for processing it and an applicable condition for processing special category data.^[7]

An employer should therefore avoid sharing an employee’s entire personnel or medical file with an external investigator where only a small amount of information is relevant.

Instead, the employer should consider what information is genuinely necessary for the investigator to understand the allegation and conduct the agreed enquiries.

Access to investigation reports, photographs and video should also be appropriately restricted, and evidence should not simply be retained indefinitely.

Why Is Medical Context Important?

An employer should consider the medical context before deciding that apparently inconsistent behaviour amounts to dishonesty.

Health conditions can affect people in very different ways. Symptoms may fluctuate and a person’s capabilities may change from day to day.

An employee with chronic pain might have periods where they can carry out certain activities followed by periods where those activities become difficult. Someone experiencing workplace-related stress may be capable of social or recreational activity outside the environment contributing to their condition.

Disability also needs particular consideration.

Under the Equality Act 2010, employers can have a duty to make reasonable adjustments for disabled workers. Acas advises employers to consider reasonable adjustments where sickness absence or difficulties returning to work are related to disability.^[8]

It is therefore important to distinguish between suspected dishonesty and a genuine capability, health or disability issue.

What Should an Employer Do If the Investigation Finds Evidence?

Finding evidence that raises further questions does not mean an employer should immediately dismiss the employee.

The investigation is only one part of the employer’s decision-making process.

The employee should normally be given a fair opportunity to respond to the allegation and explain the evidence.

An apparently suspicious situation may have an explanation that was not available to the employer or investigator. Alternatively, the employee’s response may reinforce concerns that they deliberately provided misleading information.

The Acas Code of Practice states that employers should carry out necessary investigations to establish the facts and allow employees to put their case before disciplinary decisions are taken.^[5]

Employers should consider the investigator’s evidence alongside employment policies, contractual terms, medical information and the employee’s explanation. In serious cases, advice from an employment solicitor or experienced HR professional may also be appropriate.

How Can Employers Avoid Unfair Sick Leave Investigations?

One of the biggest risks is treating unusual behaviour as proof of fraud before the employee has had an opportunity to explain it.

Employers should avoid assuming that employees must remain at home, relying on isolated photographs without context or commissioning wide-ranging surveillance simply because a manager is suspicious.

They should also avoid accessing private accounts or communications without lawful authority or disregarding medical information that does not support the allegation.

A proportionate investigation should focus on answering a specific question and gathering enough reliable information for the employer to decide what should happen next.

How SPS Investigations Can Help Employers Investigate Sick Leave Fraud

At SPS Investigations, we support employers who have genuine concerns about possible sickness absence fraud, undeclared secondary employment and other forms of employee misconduct.

We can review the circumstances surrounding the concern and help establish what evidence would actually be useful. Depending on the case, this may involve lawful open-source enquiries, targeted surveillance from public places and detailed reporting of relevant observations.

Our role is to establish facts. We distinguish between what has actually been observed and what might only be assumed from those observations.

We do not diagnose medical conditions or decide whether an employee should face disciplinary action. Those decisions remain with the employer, taking into account the complete evidence, employment procedures and appropriate legal or HR advice.

We provide corporate investigation services to businesses throughout London and the Home Counties.

If you are concerned that an employee may be abusing sickness absence or company sick pay, contact SPS Investigations for a confidential discussion about how the circumstances could be investigated lawfully and proportionately.

Frequently Asked Questions

How can an employer investigate suspected sick leave fraud?

An employer can begin by reviewing absence records, fit notes, communications, sickness policies and the employee’s explanation. Where there is a credible unresolved concern, further investigation may include lawful open-source research or proportionate external investigation. Employers should keep an open mind and follow a fair disciplinary process.

Can an employer investigate someone who is signed off sick?

Yes. An employer can investigate where there is a genuine concern about possible misconduct or dishonesty. The investigation should have a legitimate purpose and use methods that are necessary, fair and proportionate.

Does an employee have to stay at home when off sick?

No. An employee who is genuinely unfit for work may still be able to shop, exercise, drive, meet other people or carry out other everyday activities. These activities do not automatically demonstrate that their sickness absence is dishonest.

Can an employee work another job while on sick leave?

In some circumstances, yes. An employee may be unfit for one type of work but capable of performing another. Employers should consider the duties involved in each role, the employee’s medical limitations and any contractual restrictions on secondary employment.

Can an employer use a private investigator for sick leave fraud?

Potentially. An employer may instruct a private investigator where there is a credible and sufficiently serious concern and external enquiries are necessary and proportionate. The investigation should focus on defined issues rather than unnecessarily monitoring the employee’s private life.

Can an employee be followed while they are off sick?

Targeted surveillance in public places may sometimes be appropriate where there are reasonable grounds for investigating serious suspected misconduct. Covert worker monitoring requires careful justification and must comply with data protection requirements.

Can social media prove sick leave fraud?

Public social media content can sometimes form part of an investigation, but it rarely proves fraud on its own. Employers should consider when the content was created, what it actually shows and whether the activity is genuinely inconsistent with the employee’s explanation or medical circumstances.

Can an employee be dismissed for fraudulent sickness absence?

Potentially. Deliberate dishonesty relating to sickness absence or sick pay may amount to serious misconduct. However, an employer should conduct a reasonable investigation, consider the employee’s explanation and follow a fair disciplinary process before deciding whether dismissal is appropriate.

This article relates primarily to employment investigations under English law and provides general information rather than legal advice. Employers should obtain appropriate employment law, HR and data protection advice where necessary.