What Documentation and Evidence do I Need to File a Personal Grievance?

Filing a personal grievance is one of the more serious steps an employee can take when something has gone wrong at work. To succeed, your claim must be persuasive and persuasion in the Employment Relations Authority (ERA) or Employment Court rests heavily on evidence. Documents, witness testimony, notes and records will be important to support your case.  Knowing what to include and what will be acceptable can be tricky.  Working with an advocate to compile your case can make the difference in achieving a positive outcome.   

Why do documentation and evidence matter?

When you lodge a personal grievance, either for unjustified dismissal, unjustified disadvantage, discrimination, harassment, or constructive dismissal, the key question is ‘did your employer do something wrong, and can you prove it?’  The ERA and Court decide on the merits not theoretical fairness. They look at what actually happened.  Without credible evidence, even a case that seems obviously unfair may fail.  Your documentation helps show chronology, consistency, causation, and the impact of what happened and it allows you to respond to the employer’s version, challenge any counter‑evidence, and provide a coherent narrative.  A good claim is built on a foundation of evidence, not just strong feelings or assumptions.

What types of documentation and evidence should you collect?

Here's a guide to what kinds of material can make a difference to your case:

Type of Evidence	Why It Helps	Tips for Collecting/ Preserving
Employment contract, policies, job description, staff handbook	These set out what your mutual obligations are (hours, performance, process, policies).	Get the version that applied at the time of the issue. If your employer refuses, request formally.
Pay slips, payroll records, timesheets, rosters	To show hours worked, wages owed, overtime, reductions, or discrepancies.	Keep originals or prints and preserve digital versions (screenshots, PDFs).
Emails, text messages, WhatsApp messages, letters, memos	These often provide statements, promises, threats or instructions relevant to the incident/issue.	Save the full threads, including timestamps, sender, recipients. Don’t delete them.
Meeting notes, diaries, logs	If you record conversations or events, those notes can help you reconstruct events.	Be factual, time-stamped and objective.
Witness statements or affidavits	Co‑workers, supervisors, or others may corroborate your version of events.	Get written, signed statements. Ask them to include their recollection, contact info, and dates.
Performance reviews, warnings, disciplinary records	To show any pattern, or to refute claims your performance was poor.	Secure all documents, even drafts or informal feedback.
Employer’s correspondence, memos, letters, investigation reports	To see how your employer handled issues, what they considered, what they decided.	Request full copies, even redacted ones.
Medical records, doctors’ notes, counselling or psychological assessments	Particularly if there is a health impact, stress, or a medical cause/effect link.	Ensure you have any consents needed. Keep originals or certified copies.
Records of lost wages, other financial losses	Payslips, bank statements, invoices to show what you lost because of your employer's action.	Be precise with dates, amounts, and connection to the employer’s conduct.

You want evidence that is reliable, is relevant and related to the incident, and coherent. A note made months later is weaker than something recorded at or near the time. An email dated at the time is stronger because it reflects an immediate reaction.

Why is the timeline important?

One of the most powerful tools in your case is a timeline. Piecing together a clear chronological account of what happened day by day and incident by incident makes your story easier to follow and harder to discredit.  In many disputes, it is the gaps or unexplained inconsistencies that damage the employee’s credibility. A well‑constructed chronology fills in gaps or shows where they remain, making your version more plausible.

How an employment advocate can help you with documentation and evidence?

While you can pursue a personal grievance on your own, an employment advocate brings critical value especially in relation to evidence. Here’s how:

Case assessment and evidence mapping

An experienced advocate will help you map out what evidence is available, what is missing, and what gaps need to be closed. They can help you see weak spots you might not notice.

Formal requests and disclosure

Advocates know the legal steps to formally request disclosure from your employer (for example, internal emails, investigation notes, meeting minutes, performance files). They can negotiate or demand access where your informal request may be ignored.

Structuring exhibits and affidavits

They can help you convert raw documents into exhibits, structure witness affidavits (statements), and ensure they comply with the rules (signing, verification, formatting). A well‑drafted affidavit or witness statement is more persuasive.

Preserving and securing digital evidence

Advocates can help you take precautions such as making forensic copies (safe backups), preventing auto-deletion, avoiding tampering, and advising you on chain of custody. Digital evidence is delicate and can be challenged, so careful handling matters.

Chronology construction and narrative development

While you may have notes and pieces of evidence, an advocate can help you weave them into a coherent narrative and timeline, anticipating the employer’s counter‑arguments and preempting inconsistencies.

Cross‑examining or challenging employer evidence

When your employer produces documents, advocates can help you spot red flags (e.g. inconsistencies, missing pages, suspicious redactions) and raise challenges to reliability or completeness.

Strategy advice on admissions, settlement, and risks

They can guide whether to push for admissions, which documents to emphasise, and how to approach settlement negotiations (what evidence to show, what to hold back). They also help you assess risk and if your gaps are irreparable, they may advise you differently.

Representation at mediation, ERA or Court

Finally, having an advocate speak for you means someone with experience in evidence law is proactively presenting and defending your evidence. That can make a big difference in how credible your case appears.

In practice, when you prepare a personal grievance, your advocate will help you:

1. Map out your claim including which grounds you are relying on,

2. Identify necessary evidence and request or gather it,

3. Construct a narrative (with chronology) that links employer conduct with harm and proposed remedy,

4. Anticipate the employer’s counter‑arguments and gather rebuttal evidence,

5. Decide what to show in mediation, ERA, or court including what to emphasise and what to hold back,

6. Use the rules of evidence such as admissibility, hearsay challenges, authentication, spoliation arguments to benefit your case, and

7. Negotiate or settle, if possible, using the strength of your evidence to leverage an outcome.

In short, you may collect a lot of material but without the right legal lens, it may remain under‑utilised. An advocate helps you shape your evidence into a persuasive case.

FAQs: Collecting Evidence and Documents in a Personal Grievance

Below are some frequently asked questions about evidence and documentation in personal grievance claims.

“Can I use informal notes or diary entries I made?”

Yes, but their weight depends on timing, detail, and consistency. Notes made right after a meeting or incident are stronger than those made weeks later. Note entries are generally best used to supplement stronger evidence, not as a stand-alone claim.

“What if the employer refuses to give me internal documents?”

You can formally request disclosure. If refused, your advocate or lawyer can apply to the ERA or Court to compel disclosure. The ERA has powers to order production of evidence. Also, refusing disclosure may be viewed negatively by the Authority.

“Do I need to have witnesses?”

While not every case needs external witnesses, credible witnesses help reinforce your version of events and counterbalance your own testimony. The more independent and reliable the witness, the better.

“Can I rely on text messages, WhatsApp or social media chats?”

Yes.  These are valid evidence, provided they are authentic (you can show sender, timestamp, recipients) and not tampered with. Preserve screenshots, metadata, and consider making backups of the conversation logs.

“What standard of proof is required?”

The standard is “balance of probabilities” (i.e. more likely than not). You must present credible, consistent, and supported evidence that satisfies this test.

“Can I lodge a claim even if I don’t have every document yet?”

Yes.  But you must show you are actively seeking the missing documents, explain why they are missing, and show that your case is otherwise supportable. Courts expect you to act reasonably in gathering evidence.

“What happens to my documents and evidence if the case goes forward?”

They’ll be disclosed to the employer (in part or full), relied on in arguments, and become part of the official record. Maintain copies and keep them organised (exhibits, bundles) so you can reference them quickly.

With strong, coherent documentation and evidence, your case gains clarity, reduces uncertainty, and is more likely to be resolved favourably often before a full hearing. If you’re exploring whether to bring a personal grievance, treat evidence as your foundation. The best legal or emotional arguments cannot replace a credible record. Gather what you can right away, organise it carefully, and get expert support.

An employment advocate can make the difference between a disorganised packet of documents and a disciplined, persuasive case. An advocate helps you see not just what evidence you have, but how to use it, how to fill gaps, and how to present it strategically. If you are looking at filing a personal grievance, or already have one underway, get in touch with an expert for a free consultation on your case. Call now to get support from an advocate for preparing and filing your case for the best outcome. MathewsWalker.co.nz | 0800 612 355

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