When the Complainant Becomes the Respondent: How HR Should Manage Overlapping Workplace Investigations

Workplace complaints do not always happen one at a time.

An employee raises a complaint about another member of staff.

That complaint is being investigated.

Then a separate employee makes an allegation against the original complainant.

What should HR do?

Should the second complaint be delayed?

Should both matters be investigated together?

Does investigating the original complainant create a risk of retaliation or victimisation?

Or could failing to investigate the second allegation create an equally serious problem?

A recent Workplace Relations Commission decision involving an employee of a SuperValu store provides a useful example of how employers should approach overlapping workplace investigations.

The WRC ultimately rejected the employee’s claims of discrimination, victimisation and penalisation.

But the decision provides several practical lessons for HR teams dealing with multiple complaints involving the same employees.

WRC Case Reference

Adjudication Reference: ADJ-00063277
Respondent: Smiths Supervalu
Adjudication Officer: Niamh O’Carroll
Decision Date: 9 September 2026

The case involved three complaints:

CA-00073835-001 — Employment Equality Acts: discrimination
CA-00073835-002 — Employment Equality Acts: victimisation
CA-00073835-003 — Protected Disclosures Act: penalisation

All three complaints were found not well founded.

What Happened?

The employee had complained that a colleague subjected him to homophobic treatment.

The employer investigated that complaint.

The WRC records that the investigation was completed within ten working days and that the complaint concerning homophobic language was upheld.

The colleague involved resigned before any disciplinary process could be completed.

A separate issue then arose.

Another employee had made a complaint alleging inappropriate touching and comments by the original complainant at a staff Christmas party.

The employer also investigated that allegation.

The original complainant believed that this second process was retaliatory and that the organisation was creating obstacles because he had previously complained about homophobic harassment.

The WRC did not accept that conclusion.

Importantly, the Adjudication Officer found that the second employee was entitled to make a complaint and that the employer was entitled — and indeed required — to investigate it fairly.

That is the starting point for employers dealing with overlapping workplace complaints.

1. Making a Complaint Does Not Prevent an Employee From Being Investigated

An employee who has raised a grievance, discrimination complaint or other workplace concern still has the same responsibilities as everyone else.

If a separate allegation is subsequently made against that employee, the organisation may still need to investigate it.

The fact that somebody is a complainant in one process does not give them immunity from another.

But it does change the risk profile.

If the second investigation follows closely after the employee has raised a serious complaint, they may perceive it as retaliation.

HR therefore needs to be able to demonstrate something very clearly:

The second investigation exists because a separate allegation was made and requires investigation — not because the employee exercised their right to complain.

In ADJ-00063277, the WRC found that the later complaint did not establish that the employer had fabricated or procured the allegation for a discriminatory or retaliatory purpose.

2. Establish the Chronology First

When complaints overlap, chronology becomes critical.

Before deciding how to structure the processes, HR should establish:

• when each alleged incident occurred;
• when each concern was first raised;
• whether it was first raised verbally or in writing;
• who received it;
• when HR or management became aware of it;
• when an investigation was authorised;
• who made that decision; and
• what employment decisions followed.

This matters because arguments about retaliation often become arguments about timing.

In this case, evidence was given that the complaint concerning alleged inappropriate conduct at the Christmas party had been formally submitted before the original employee’s written complaint concerning the other colleague.

The original employee maintained, however, that he had raised concerns verbally before that.

The wider HR lesson is important:

The date of the formal complaint is not necessarily the beginning of the chronology.

If an employee raises a concern verbally, HR should record it.

3. Keep the Two Investigations Separate

Where the same employee appears in two different complaints, there can be a temptation to merge everything into one workplace dispute.

That is usually dangerous.

Consider two separate questions:

Investigation A

Did another employee subject this worker to discriminatory harassment?

Investigation B

Did this worker engage in inappropriate conduct towards somebody else?

Those questions may involve some of the same people or background.

But they are not the same allegation.

Each investigation should have its own:

• terms of reference;
• allegations;
• evidence;
• witnesses;
• response from the person concerned;
• findings; and
• outcome.

Otherwise, the organisation risks allowing evidence from one dispute to influence another.

4. Do Not Turn the Investigation Into a Contest Between Employees

One of the risks with overlapping complaints is that the process gradually becomes:

“Which employee do we believe?”

That is the wrong question.

An investigator should instead ask:

What can we establish about this particular allegation?

An employee may genuinely have experienced harassment themselves while also being accused of inappropriate behaviour towards somebody else.

Those two possibilities are not mutually exclusive.

Likewise, an allegation made against a complainant does not retrospectively undermine the complaint they previously made.

In the SuperValu case, the original complaint about homophobic language was upheld.

That did not prevent the employer from subsequently investigating another allegation involving that employee.

The WRC treated the processes separately.

5. A Second Complaint Is Not Automatically Retaliation

Timing matters.

But timing alone does not prove retaliation.

In this case, the employee argued that the allegation against him was part of an attempt to obstruct or retaliate against him after he complained about homophobic treatment.

The WRC found that the evidence did not establish this.

The Adjudication Officer noted that the second employee was entitled to make a complaint even though the alleged incident had taken place several months earlier.

The fact that somebody waits before making a complaint does not, by itself, establish that the allegation is fabricated.

For HR, the appropriate response is not to assume either:

“This must be retaliation.”

or:

“This cannot possibly be retaliation.”

Instead, test the process.

Ask:

• Who made the second complaint?
• When was it first raised?
• How did management become aware of it?
• Was there evidence supporting a decision to investigate?
• Who authorised the investigation?
• Was the person who made the earlier complaint treated differently because of that complaint?
• Would the employer investigate the same allegation if it involved another employee?

Those questions should be answered before the second investigation progresses too far.

6. You Do Not Need to Prove the Allegation Before Investigating It

Another useful point from ADJ-00063277 concerns the employee’s argument that he had not been given independent proof of the allegation made against him.

The WRC rejected the idea that the employer needed to prove the allegation before opening an investigation.

The employee had been informed of the substance of the allegations, attended an investigation meeting, was permitted to give his account and was allowed to record at least part of the process.

The Adjudication Officer found that the employer was entitled to put witness statements or accounts to him and was not required to establish the allegation independently before investigating it.

That distinction is fundamental.

An investigation exists to establish what happened.

HR does not need a completed finding before deciding whether a sufficiently serious allegation requires examination.

The correct question at the beginning is:

Is there an allegation that requires a fair investigation?

Not:

Can we already prove it?

7. But the Employee Must Know the Substance of the Allegation

While proof is not required before an investigation begins, fair procedure still matters.

The person responding to the allegation needs sufficient information to understand the case being put to them.

That generally means clarity around:

• what conduct is alleged;
• approximately when it occurred;
• where it occurred;
• who was involved;
• what policy or standard may be relevant; and
• what evidence they are being asked to respond to.

In ADJ-00063277, the WRC found that the employee had been informed of the substance of the allegation and given an opportunity to provide his account.

That is the distinction HR should maintain:

You do not need to prove an allegation before investigating it.

But:

You do need to give the employee a fair opportunity to understand and answer it.

8. Independence Becomes More Important When Complaints Overlap

Where one employee is both complainant and respondent across different workplace investigations, the structure of the process needs particular attention.

HR should consider:

• whether the same investigator should handle both matters;
• whether the investigator has already made credibility findings concerning one of the parties;
• whether a manager involved in the first complaint is also making decisions about the second;
• whether confidential information from one process could influence the other;
• and whether an independent external investigator would provide greater confidence in the process.

There is no rule that every overlapping complaint requires separate external investigators.

The important issue is whether each investigation can demonstrate fairness and impartiality.

9. Protect the Information Boundaries Between Investigations

Overlapping workplace investigations can create significant information-management problems.

People involved in Investigation A may know things that are irrelevant to Investigation B.

Managers may begin discussing both matters together.

Witness accounts may accidentally be shared between processes.

An investigator may become aware of background information that influences their assessment of an unrelated allegation.

HR should therefore decide:

Who needs to know what?

Consider:

• separate investigation files;
• clearly defined terms of reference;
• restricted access to evidence;
• separate witness interviews where appropriate;
• clear communication to managers;
• and careful consideration before transferring findings from one process into another.

The fact that information exists does not automatically make it relevant to every related investigation.

10. Complaints Raised During an Investigation Need to Be Identified Properly

Another useful aspect of the decision concerned comments the employee said colleagues had made about his sexual orientation and sex life at the Christmas party.

He discussed those matters during an investigation meeting.

However, he accepted that he had not made a formal complaint about them.

The WRC found that the evidence did not establish that the employer had failed to act on a clearly formulated complaint that it knew, or reasonably should have known, required a separate investigation.

This creates an important practical issue for investigators.

During an investigation interview, an employee may disclose something that sounds like a new allegation.

Do not simply continue with the interview.

Clarify:

“Are you raising this as a separate complaint that you want the organisation to investigate?”

If the answer is yes, it should be documented and referred into the appropriate process.

That can prevent later disagreement about whether HR knew a complaint had been made.

11. Delay Does Not Automatically Mean Discrimination or Retaliation

The employee also complained about delays in receiving investigation reports.

The WRC acknowledged that delay can understandably cause frustration.

But it found that delay alone did not establish discrimination or victimisation.

There needed to be evidence connecting the delay to the employee’s sexual orientation or to a protected act.

For employers, however, this should not be interpreted as permission for investigations to drift.

Delay creates other problems:

• memories become less reliable;
• witnesses may leave;
• relationships deteriorate;
• confidence in the process falls;
• employees may remain suspended or distressed;
• and allegations of deliberate delay become easier to make.

Employers should therefore set realistic investigation timelines and communicate where those timelines change.

12. Separate Investigation From Disciplinary Action

The first complaint in this case was upheld.

However, the employee who was the subject of that complaint resigned before the employer could conclude any disciplinary process.

The WRC accepted that disciplinary sanctions could not subsequently be imposed on somebody who was no longer an employee.

This illustrates another distinction employers should maintain.

Investigation

What happened?

Disciplinary process

What employment consequence should follow from the investigation findings?

An investigation finding does not itself constitute a disciplinary sanction.

The investigation establishes facts.

Any later disciplinary process deals with the consequence.

Keeping those stages separate helps protect fair procedure.

13. Not Every Workplace Complaint Is a Protected Disclosure

The employee also relied on a report to An Garda Síochána concerning what he described as threats, homophobic comments and a hostile working environment.

The WRC found that the information said to constitute the protected disclosure had not been identified with sufficient precision.

The decision also noted that, insofar as the report related to the employee’s own interpersonal workplace grievance, it did not become a protected disclosure without evidence of a relevant wrongdoing extending beyond that grievance.

This is another useful process distinction for HR.

A matter may involve:

• a grievance;
• discrimination;
• victimisation;
• bullying or harassment;
• a protected disclosure;
• or several of these simultaneously.

Do not classify it solely by the employee’s chosen terminology.

Look at the information being disclosed and identify the correct process.

A Practical HR Framework for Overlapping Workplace Investigations

When an employee involved in one workplace complaint becomes involved in another, HR should work through the following questions.

Chronology

When was each issue first raised?

Include verbal complaints as well as formal written complaints.

Scope

What exact allegation is each investigation determining?

Avoid broad terms such as “workplace conflict” where specific allegations can be identified.

Separation

Are the two investigations being kept sufficiently distinct?

Independence

Who should investigate each complaint?

Could prior involvement compromise perceived impartiality?

Evidence

What evidence relates to each allegation?

Do not allow unrelated evidence to contaminate another process.

Fair procedure

Has the person responding to the allegation been clearly told what they are being asked to answer?

Retaliation risk

Would the second investigation have happened if the employee had never made the first complaint?

New complaints

Has an employee raised another issue during an investigation interview?

If so, clarify whether they want it treated as a formal complaint.

Communication

Do employees understand which process they are currently participating in?

Outcome

Who receives the investigation findings, and what process follows if an allegation is upheld?

The WRC Outcome

The employee brought three complaints arising from the employer’s handling of the workplace issues.

Discrimination

CA-00073835-001

The WRC found that the employee had not established facts from which discrimination on the sexual-orientation ground could be presumed.

The complaint was not well founded.

Victimisation

CA-00073835-002

The WRC accepted that complaining about homophobic treatment constituted a protected act under the Employment Equality legislation.

However, the employee did not establish that the subsequent investigation or other alleged adverse treatment had been caused by that protected act.

The complaint was not well founded.

Protected Disclosure Penalisation

CA-00073835-003

The WRC found that the evidence did not sufficiently identify a protected disclosure and, even if one were assumed, did not establish that the employer had penalised the employee because of it.

The complaint was not well founded.

The Practical Lesson for Employers

The fact that an employee has made a workplace complaint should not prevent a genuine allegation against them from being investigated.

But overlapping workplace investigations require careful process design.

The employer should be able to demonstrate:

Why each investigation exists.

When each complaint was raised.

What allegation each process is deciding.

Who is responsible for investigating it.

What evidence belongs to each process.

And why one complaint has not influenced the treatment of another.

The aim is not to decide who the “complainant” and “respondent” are overall.

Those roles may change from one process to another.

The aim is to ensure that each allegation receives its own fair, independent and evidence-based examination.

For HR teams, that is the real lesson from ADJ-00063277.

How Employment Matters Can Help

Employment Matters supports employers with complex workplace processes, including:

• Independent Workplace Investigations
• Workplace Mediation
• Performance Management
• Defending a Legal Claim
• Redundancy and Dismissal
• Training and Workshops

Where several complaints, grievances or investigations overlap, getting the structure right at the beginning can prevent one process from undermining another.

This article is for general information purposes only and does not constitute legal advice.