What the claims are about

The allegation at the centre of every diesel emissions claim is the same. It is said that vehicles were fitted with software or engine management strategies that caused the emission control system to work properly during official testing and less well in ordinary driving, so that the vehicles produced more nitrogen oxides on the road than their approval documents implied. Devices of that kind have a name in law. Article 5(2) of Regulation (EC) No 715/2007, which is assimilated law in the United Kingdom, provides that the use of defeat devices that reduce the effectiveness of emission control systems is prohibited, subject to narrow exceptions for protecting the engine, starting the engine, and conditions covered by the test procedures.

Nitrogen oxides, usually written as NOx, are a group of gases associated with respiratory harm and with poor urban air quality. They are the subject of these claims. Carbon dioxide, fuel economy and the vehicle’s road tax band are different questions and are not what these proceedings are about.

Which proceedings exist, and against whom

The reliable list is the Court of Session’s own register of group proceedings, which records each set of proceedings that has been granted permission, the representative party, the solicitors acting, and the description of the group. As at 14th August 2026 the register includes separate NOx emissions group proceedings concerning vehicles of the Mercedes-Benz group, the Vauxhall and Opel group, the BMW group, the Peugeot, Citroën and DS Automobiles group, Jaguar Land Rover, the Fiat and Chrysler group, the Volkswagen group including Audi, Skoda and Seat, Ford, and the Nissan and Renault group.

Two things about that list matter more than the names on it. First, each set of proceedings is separate, with its own representative party, its own solicitors and its own court reference. There is no single Scottish diesel action. Second, each is defined by reference to particular vehicles, in most cases diesel vehicles meeting the Euro 5 or Euro 6 emissions standards, and to particular periods of acquisition. Euro 5 applied to new cars registered from 1st January 2011 and Euro 6 to new cars registered from 1st September 2015, under Article 10 of Regulation (EC) No 715/2007. Owning a diesel car made by one of those manufacturers does not by itself put you in the group. The registration document will tell you the make, model and date; a solicitor acting in the relevant proceedings will tell you whether it falls inside the description the court approved.

You are not in it until you join

This is the point that costs people their claims. Group proceedings in Scotland are opt-in. Section 20(7) of the 2018 Act permits rules to allow opt-out proceedings, but no act of sederunt has yet done so, and rule 26A.1 of the Rules of the Court of Session defines a group member as a person who expressly consents to the proceedings being brought on his or her behalf. Nobody is claiming for you by default, and no settlement reached in any of these proceedings will reach you automatically.

Joining means giving notice in the prescribed form to the representative party, under rule 26A.14, so that your name is entered on the group register kept under rule 26A.15. There is a deadline that has nothing to do with the general law: the court’s order granting permission specifies the period during which claims may be brought into the proceedings, under rule 26A.12. That period can close long before your own legal time limit expires. Our page on how group proceedings work in Scotland sets the procedure out in full.

The legal basis in Scotland is not the English one

Diesel claims are usually framed on three overlapping bases: that the buyer was misled about the vehicle, that the vehicle was not of the quality the contract required, and that a statutory prohibition was breached. All three look different in Scots law.

On misrepresentation, the statute that English pages cite does not apply here at all. Section 6 of the Misrepresentation Act 1967 provides that the Act does not extend to Scotland. The Scottish provision is section 10 of the Law Reform (Miscellaneous Provisions) (Scotland) Act 1985, which removed the old rule that damages for misrepresentation inducing a contract could be recovered only where the misrepresentation was fraudulent. Fraudulent misrepresentation remains a separate and harder case to make.

On contract, the position depends on when the vehicle was acquired and from whom. For consumer contracts entered into on or after 1st October 2015, section 9 of the Consumer Rights Act 2015, which applies across the United Kingdom, treats every contract to supply goods as including a term that the quality of the goods is satisfactory, and section 9(3) makes it explicit that quality includes safety and durability as well as fitness for purpose. For earlier contracts the equivalent is section 14(2) of the Sale of Goods Act 1979. A contract claim lies against the party you contracted with, which for most people is the dealer rather than the manufacturer, and that is one reason these claims are also framed in delict against the manufacturer.

On statutory duty, the prohibition in Article 5(2) of Regulation (EC) No 715/2007 is the anchor. Whether and how a breach of it gives an individual buyer a right to damages in Scots law is one of the questions these proceedings exist to decide, and it has not been decided.

If you have already sold the car

Having sold or returned the vehicle does not by itself end a claim, because the loss complained of is generally said to have been suffered at the point of acquisition: the vehicle is said to have been worth less than was paid for it. Whether a person who has since disposed of the vehicle falls within a particular group depends on how the court defined that group when it granted permission, and the definitions are not identical across the proceedings. It is a question to ask specifically rather than to assume. The same applies to leased vehicles, to vehicles bought used, and to vehicles bought by a business rather than a consumer, where the Consumer Rights Act does not apply.

The time limit is the thing to check first

A diesel claim is a claim for financial loss, not for personal injury, so the relevant rule is the five-year negative prescription. Under section 6 of the Prescription and Limitation (Scotland) Act 1973, an obligation to pay damages is extinguished if it subsists for five continuous years without a relevant claim. Section 11(1) starts that period at the date the loss occurred, and section 11(3) postpones the start where the creditor was not aware, and could not with reasonable diligence have been aware, of the relevant facts. In diesel claims the date of awareness is precisely what is in dispute, and it is not something a web page can settle for your vehicle.

What it costs, and the risk if the action fails

These claims are ordinarily funded by a success fee agreement under Part 1 of the 2018 Act, often with third party litigation funding and insurance behind it. The statutory ceiling matters, because a diesel claim is not a personal injury claim. Under the Success Fee Agreements Regulations 2020 the cap for personal injury claims is tiered from twenty per cent downwards, but for other civil proceedings the cap is fifty per cent of the financial benefit. That is a ceiling rather than a rate, and agreements are often written well below it, but you should know the figure in your own agreement before you sign it.

The protection against paying the other side’s expenses is also narrower here than in an injury claim. Section 8 of the 2018 Act, qualified one-way costs shifting, applies where the person bringing the proceedings makes a claim for damages for personal injuries or for a death from personal injuries. A claim for the diminished value of a car is neither. Ask what arrangement is in place for adverse expenses, whether insurance has been taken out, who pays the premium, and what happens to it if the action succeeds. Our page on what no win no fee actually means in Scotland explains the funding rules in general.

Who does this work

The Court of Session’s register names the solicitors acting in each set of proceedings, and it is public. Firms also advertise heavily for these claims, which is a feature of the procedure rather than a warning sign: section 20(6)(b) of the 2018 Act requires a representative party to satisfy the court that all reasonable efforts have been made to identify and notify potential group members, and advertising is how that is done. It does mean that an advertisement is not evidence that any particular proceeding covers your car.

Tell us what you bought and when, and we will pass your details to one of our member firms, who will be in touch. If no group proceeding covers your vehicle, we will say so rather than send the enquiry anyway. You can check any Scottish solicitor on the Law Society of Scotland’s public roll yourself.

Sources

• Register of group proceedings in the Court of Session, Scottish Courts and Tribunals Service
• Regulation (EC) No 715/2007, Article 5 on defeat devices, and Article 10 on the Euro 5 and Euro 6 dates, legislation.gov.uk
• Civil Litigation (Expenses and Group Proceedings) (Scotland) Act 2018, section 20, and section 8 on qualified one-way costs shifting, legislation.gov.uk
• Rules of the Court of Session, Chapter 26A: group procedure, Scottish Courts and Tribunals Service
• Law Reform (Miscellaneous Provisions) (Scotland) Act 1985, section 10, and Misrepresentation Act 1967, section 6, legislation.gov.uk
• Consumer Rights Act 2015, section 9, legislation.gov.uk
• Prescription and Limitation (Scotland) Act 1973, section 6 and section 11, legislation.gov.uk
• Civil Litigation (Expenses and Group Proceedings) (Scotland) Act 2018 (Success Fee Agreements) Regulations 2020, SSI 2020/110, legislation.gov.uk

This page explains the law in general terms and is not advice on your own situation. It states the position as at 14th August 2026. The proceedings described are live and the register changes as permission is granted or refused; the deadline for joining any particular group is set by the court’s own order. Take advice from a solicitor about your vehicle and your time limit before relying on anything here.