How Can I Prove My Case?

Once you have decided that you want to legal action, there is a law you can base your claim on, you are able to take legal action and you have identified the right defendant, you will have to prove your case.

By «prove your case», we mean that you will need to:

(i) Have evidence that supports your «version of events» (i.e. what you are saying has happened); and

(ii) Have a strong legal argument that shows that your version of events has involved a breach of the law.

Only when you prove your case can you get a judgement in your favour and secure a remedy.


Who Has to Prove their Case?

A key concept in legal cases is the «burden of proof«. The burden of proof dictates who need to prove their case. It’s important you know who has the burden of proof before taking legal action.

(a) Civil Cases

If you bring a civil claim, you will need to provide evidence to support your claim. In other words, you have the “burden of proof” to prove your claim.

To succeed, you will need to:

  • Produce evidence before the court about to show the defendant committed the acts you have complained of, and the consequences of those actions.
  • Show the defendant is responsible for the harm you suffered as a result of those actions.

Focus Point: A Shifting Burden of Proof

In some cases, the burden of proof can shift to the defendant. For example, in discrimination cases in many jurisdictions, the claimant has the burden of proof to show that the defendant treated them differently to persons in a similar position on the basis of a protected characteristic (e.g. race, sex). However, when the claimant proves this, the burden of proof shifts to the defendant to show there was is a legitimate and reasonable explanation for the differential treatment.

The shifting of the burden of proof in these cases makes it easier for the claimant to prove their case.

(b) Criminal Cases

Usually, the public prosecutor (the state official seeking to convict the defendant) has the burden of proof to prove that a crime was committed and the crime was committed by the defendant. To prove this, they rely on investigative authorities like the police to collect evidence.


What do You Have to Prove?

If you have the burden of proof, you have to prove that all the «elements» of the crime or civil wrong your claim is based on have been committed and that the defendant is responsible. Elements are the ingredients of the crime or civil wrong. They are the key acts, omissions, states of mind or circumstances that must occur for the crime/civil wrong to have been committed.

Identifying the elements that apply to your case is a key part of your legal analysis. Once you identified the laws that your claim could be based on (see What Laws Can I Enforce?), it is important to conduct research to find out the elements and make a provisional analysis on whether they could be proven in your case.

Once you have identified the elements, you have to prove that they have occurred to the appropriate «standard of proof«. This is the level of certainty with which you need to show that the crime/civil wrong was committed.

Key Points:
You will need to have evidence that shows:

  • What: What was the nature of the harm? (e.g. pollution or physical injury)
  • Where: Where did the harm take place? (e.g. the town, river, region)
  • When: when did the harm occur, or is it still happening?
  • How: How was the harm caused?
  • Who: What businesses or individuals were involved in the activity that caused the harm?

(a) Civil Cases

The standard of proof in civil cases is often called the «balance of probabilities«. This means that you have to prove that it is more likely than not that the elements of the civil wrong your claim is based on has been committed.

What exactly you will need to prove will depend upon the type of civil claim that you bring. Below is an example:

The Elements of a Breach of Contract Claim

  • 1

    There is a contract

    In essence, this means you have to show one party to the contract offered the other party someone of value (e.g. money) for something in return (e.g. a service). You also need to show what the "terms of the contract" were (i.e. what precisely was agreed). For example, the defendant promised to pay you to build a wall.

  • 2

    There was performance of the contract

    This means that you held up your end of the deal. For example, you built the wall in the agreed time.

  • 3

    There was a breach of the contract

    This means that the defendant did not do what they said they would do in the contract. For example, they did not pay you for building the wall.

  • 4


    You need to show the breach of contract caused you loss or damage. For example, the defendant's failure to pay you caused you to fall into debt.

  • 5

    Loss and damage

    To get a full remedy for the harm caused, you need evidence of the specific harm that flowed from the breach of contract.

(b) Criminal Cases

The standard of proof in criminal cases is often caused «beyond reasonable doubt«. This means that the judge or jury has to be «sure» that the defendant committed the elements of the crime. This is a high level of certainty that means it can be difficult to successfully prove criminal cases.

The prosecuting authorities have to prove beyond reasonable doubt that:

  • All the elements of the criminal offence occurred
  • The defendant committed the offence

These elements and the tests of causation (what is needed to show the defendant was responsible) depend on the particular criminal offence as defined in the criminal code.

For example, if the offence of theft is defined as “the taking of another person’s property without that person’s permission, with the intent to deprive the owner of it”, a prosecutor would need to prove the following elements:

The Elements of Theft

  • 1

    The property existed

    It has to be proven that the thing you are arguing was stolen existed at the time. For example, there was 5 cattle in a certain field.

  • 2

    The property belonged to someone other than the thief

    It must be shown that the property allegedly stolen was not the thief's. For example, you owned the cattle.

  • 3

    The property was taken

    For example, the cattle were taken from the field.

  • 4

    The owner did not consent

    For example, the owner of the cattle did not want the cattle to be taken away.

  • 5

    The property was taken with intent to deperive

    This means that the defendant meant to steal the property. They did not take it by accident or think it was ok for them to take it. For example, the defendant knew that the cattle belonged to you and he was taking them without your consent.


How Can I Gather Evidence?

Once you know what you need to prove, you need to gather evidence to show that the crime or civil wrong was committed. Collecting evidence takes time and may involve contacting and meeting people (victims, witnesses, experts etc.), or going to the place where the wrong was committed. When collecting evidence to support your case, you have to respect the law and the rights of others (e.g. the right to privacy). Evidence obtained unlawfully often cannot be used in court.

The section will give you a brief overview on evidence gathering techniques. For more information, look out for the upcoming A4J Evidence Gathering Guide.

(a) Gathering Information about the Person/Organisation I Want to Sue

Before starting your research, it is important to decide which part individual company you want to sue (see Who Can I Sue?). If you add the want defendant to your claim, you may be able to amend this at a later date but it could lead to your case being struck out or dismissed. That’s why, if it is not clear who the precise identity of the defendant is, that you gather evidence to find this out.


(i) Finding Information about a Company/Organisation

Careful research is needed to ensure you have identified the correct target and that the company is worth suing (i.e. does it have enough assets to pay compensation?).

Names of people, companies and organisations are sometimes difficult to find.

  • In most countries, companies should not have a name that is identical or similar to the name of another company. But scam companies may use names that are almost identical to names of well-known companies with a good reputation. Check if this has happened in your case.
  • Rules on business secrets can make it difficult to find out details on companies’ activities and owners.
  • It also may often be difficult to obtain reliable information about the real economic worth of the company.

The following sources of information may help you overcome these obstacles:

Company and business registers

Business registers may be produced by public or private bodies.

Using the register, members of the public can generally find out;

  • Whether a company exists as a legal person
  • Who is authorised to represent the company and sign contracts
  • Some information about the financial state of the company

The content of company registers is usually regulated by law, and the information provided varies from country to country.

Sometimes fees are charged to access a register. If the fees are very high, you could ask (pro bono) corporate lawyers to help you; they often have annual subscriptions to company registers since they use them everyday.

Key Resources:

For further information on company registers, see:

State-owned companies

The main legal documents for state-owned companies may not be available in company registers, but may be held by the public bodies which set up the company.

In some countries, the organisational structure and operational rules of a state-owned company may be defined and detailed by national legislation.

Other “legal persons”: associations, foundations, trusts

These won’t be listed on national registers of companies, but details about such organisations may be recorded in other registers.

Some organisations are not “legal persons” and may not be registered anywhere. These are known as “unincorporated associations”. For “unincorporated associations”, you need to identify the natural persons associated with them. These individuals can be held responsible for the actions of the organisations.

Finding out who runs informal organisations can be difficult;

  • Try using a search engine or looking at the organisation’s website.
  • Try to identify affiliated organisations
  • Check the public filings that the entity has made (see the next paragraph of this section).

Company reports and filings

Companies often have to make reports and make information publicly available.

For example:

  • Companies which receive funding from the public (via the issue of securities) are generally required to make public detailed information about the company and its financial position.
  • Companies operating in regulated sectors (e.g. financial services, energy, utilities) are often required to make regulatory information public.
  • Companies are sometimes the object of investigations by public bodies, and are required to publicly disclose information in the course of those processes.


(ii) Finding Information about an Individual

If you want to take legal action against an individual (sometimes called a “natural person”), the first question is in what capacity is he/she relevant to your case? For example, are you taking legal action against someone because of their role as a director of a company? Or because they are a public official or government minister?

When you have answered that question, the following sources may provide information on the individuals in question.

Association with an organisation

If you are looking for an individual who may be the owner, representative, or office holder of a company, or other organisation, check company registers to find out information about the company.

Office-holder in a public body

When senior public office holders are appointed, information on their positions are usually published. This often appears in official journals of the country.

Freedom of information laws also cover public bodies (see Access to Information);

  • You can make information requests under these laws to obtain information about public office holders when the information relates to their public office.
  • Usually, the information that can be obtained includes the office holder’s name, the scope of his/her authority, and the date of assuming office.

Persons registers

Government bodies often hold databases which can help you research information on individuals.

For example:

  • In some countries, authorities that issue passports, identity cards, or vehicle registration, may be authorised by law to provide you with information on a particular person.
  • Public registers are kept in many countries of individuals who have been involved in a previous court case or who have been bankrupt.

You will first need to prove that you have a legal interest in obtaining information about that person.

  • Proof of a legal interest could include evidence that the individual caused damage to you and that you wish to claim compensation.

When researching individuals, their right to privacy may limit what information you can access and use.

(b) Gathering Information on the Activities of Possible Defendants

For a successful legal action, you need to know more than simply who has done something harmful. You need to know what has been done, and why and how it happened. This section outlines a number of sources that could help you find information about defendants’ activities.


(i) Public Information

You can find much useful information readily accessible in publicly available sources. Publicly available information could include:

  • Information found on a web search;
  • News articles;
  • Reports from journalists and news agencies; or
  • Reports by NGOs, government or international organisations.


(ii) Licences and Permits

In most countries, private companies and individuals can only operate certain industrial or trade activities if they obtain licences. The riskier a business is, the more licences are required and the more complex those licenses may be.

  • E.g. licenses from public bodies are required by any business that includes risks related to the environment, public health, public safety, financial stability etc.

The details of these licences are normally held by the public office charged with oversight.

Sometimes, public offices have to publish license information:

  • This information can be found on public websites, or annual reports of the public office.
  • However, such information is not always published or accessible to the public. The level of access depends on the country and public office concerned.

When public bodies are reluctant to share the information you need, you will need to make a freedom of information request or turn to other sources, such as information from non-governmental organisations or international organisations.


(iii) Public Funds and Public Contracts

Public funds and public contracts may be an important source of information for preparing your legal action. This includes Information on the financial transactions of public bodies, and individuals or companies involved in public contracts.

Try accessing this information through information requests to public bodies and through checking information in published sources.

Key Resources:

Here are some examples of useful information sources you could try:

  • Budgets of public bodies;
  • Awards of concessions and contracts (common in communications, transport and extractive industries);
  • Public procurement (process when public bodies purchase goods/services);
  • Subsidies and loans by state-owned financial institutions;
  • Privatisations or public auctions;
  • Development projects;
  • Organisations that monitor aid or development activity (e.g. Bankwatch; an organisation dedicated to monitoring use of international financial institutions operating in Central and Eastern Europe. Publish-what-you-fund; a not-for-profit organisation that campaigns for transparency in aid funding);
  • Disaster recovery funds;
  • Tax records; and
  • Revenue and incomes data (e.g. the Extractive Industries Transparencies Initiative collects information on incomes in the extractive industry in some countries).


(iv) Other Legal Cases

Other legal cases can be very important sources of information for your own legal action, where one of the defendants is involved. In any court case, evidence is provided and analysed before the court. The evidence produced in other cases can provide details about the nature of a company/person, its activities, and the broader issue.

In different countries and cases, rules vary on who can have access to courtrooms and case files;

  • Some cases take place during closed hearings.
  • Restrictions (based on the right to privacy or business secrets) may apply to information disclosed in courtrooms or in case files.

However, the right to a fair trial generally means court hearings and case files are public. Therefore, most information about court cases can be accessed by the public.

Key Resources: General Investigative Research Tools

Check out and use the following toolkits designed for investigative journalists:


What Kind of Evidence do I Need?

Documentary evidence is generally viewed as the best form of evidence. When compiling the evidence for your claim, prioritise the collection of documentary evidence.

Practical Tip
Try and get the originals of the documents that you need. If you can’t get the originals, gather evidence showing that the copy is an authentic copy of the original.

Keep paper and electronic copies of all evidence.


(i) Official Documents

Official documents are formal documents that have legal authority. These are highly reliable. These include:

  • Contracts;
  • Letters from the administration;
  • Environmental assessments; and
  • Certificates


(ii) Correspondence

Emails or letters you have with different actors (victims, the defendant, administration, organisations etc) counts as evidence.


(iii) Notes of Relevant Meetings

Write down notes on all the meetings you have with the parties involved in the case, and make them sign the notes.

  • For example, if you have a meeting with a company, write a report of all the commitments made in the meeting, and have the parties sign it, so that you can later ask them to comply with those commitments.


(iv) Medical Certificates

If you have suffered physical harm, a medical certificate, made by a doctor or other medical professionals, stating that you have suffered an injury can be useful.

  • The certificate should describe the injury and its probable cause.


(v) Reports

Research by independent experts can also be very useful.

  • The report can either be an existing report written for another purpose, or you can ask someone independent to write a new report (this can be expensive).


(vi) Photographs and Videos

It is important that the date of all photos or videos evidence is clear and available.

  • One way to do this is for the date to be indicated on the picture. The date may be registered electronically, or you can place a daily newspaper within the image to show the date the picture was taken.

It is also important that the picture or video can identify the place where it was taken;

  • It should be taken with something unique from this place, which can show that the pollution, for example, which appears in the picture, is in the place stated.
  • You could, for example, take the picture of a truck with the company’s name on it, or an identifiable building of a town next to what you want to show on the picture or the video.
  • You could also hold a GPS device in the picture, showing the coordinates.


(vii) Evidence from the Internet

You can use websites and other information found on the internet, by saving the address on a document, copying the article, printing it or even by taking a print screen.

  • Make sure to make a note of when the print was made.


(viii) Witness Evidence

Declarations made by the victims or witnesses, asserting the existence of some facts are very important (these can be called testimonies). They might be written or spoken.

While collecting the testimonies, you have to register the identity of the person who is testifying, by taking her name and identity information and having her sign the testimony.

Declarations or statements made by witnesses are very important evidence in legal cases. These are called «witness statements».

Key Resource: The A4J Guide on Witness Statements

The A4J Guide provides you with information on what should be included in witness statements, how they should be structured and formatted. This is a useful tool if you need to take a witness statement without the assistance of a lawyer.

If the person who testifies wants her identity to be kept secret, you still need to have her identity information, but you can ask the judge not to reveal this information to the accused/defendant.


The Financial Cost

Collecting evidence costs money. You will need to take this into account when deciding if you are going to undertake litigation.

The costly parts of gathering evidence include:

  • Travelling to the place where the evidence needs to be collected (e.g., to take photos or interview people)
  • Collecting physical evidence, storing it, and bringing it to court
  • Paying the transport costs for witnesses to come and give evidence in court.
  • Obtaining reports by independent experts
  • Collecting samples and analysing them (e.g. where the claim concerns environmental pollution).

For further information, see How Can I Finance my Action?


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