C650 form: challenge a children order affected by a Trimega hair-strand test
Form C650 is an application notice to vary or set aside an order about children where Trimega Laboratories Limited conducted a hair-strand drug or alcohol test in the case and you assert the result was wrong and materially affected the order.
Fill in the C650 form with Wren
How Wren helps with the C650
Official forms are written for lawyers. With Wren you do not have to decode this one on your own, and you still follow the court’s procedure.
- Plain questions, one at a timeEach part of the C650 becomes short questions in everyday words. Answer at your own pace and come back to it.
- Help beside each questionWhat the question is asking and what the official guidance says about it, in plain English.
- The official form, filled inYour answers go into the official C650. You check it, sign it and send it yourself. Nothing goes to the court for you.
- What comes next, kept with your caseWhat usually happens after you send it, with the dates worked out from the published rules.
Time and money
- On your own
- A day or more
- With Wren
- About an hour for most forms
- Solicitor for this form
- £740 to £1,2403 to 5 hours
A solicitor’s time for the C650 can run to £1,240. With Wren it is part of £19.99 a month, and it takes about an hour for most forms rather than a day or more.
Times and hours are Wren’s estimates for a typical case, not quotes. Solicitor costs are those hours at £247 an hour, the courts’ guideline rate for a solicitor with over four years’ experience, outside London (GOV.UK, Solicitors' guideline hourly rates (in effect from 1 January 2026)). The guideline runs from £200 to £295 an hour outside London depending on experience, firms set their own rates, and VAT is added on top.
Key facts
- Official title
- Application notice to vary or set aside an order in relation to children where a drug or alcohol toxicology test after 2010 was involved: Form C650
- Edition
- 11.17 (5 pages, including a statement of truth and where to send it)Source: official page (external source, opens in a new tab)
- Only for
- Cases where Trimega Laboratories Limited conducted a drug or alcohol hair-strand testSource: official page (external source, opens in a new tab)
- Decided on paper
- A judge may decide on the information in the form without a hearing; a party who objects can apply within 7 days for a hearingSource: official page (external source, opens in a new tab)
- What to attach
- A copy of the final order or the order directing the testing, if you have it, and any draft order. Other documents will not be consideredSource: official page (external source, opens in a new tab)
Who uses the C650
A party to the original children proceedings, or a local authority that wishes to use the process. GOV.UK says to use it only where Trimega Laboratories Limited carried out the test.
When it is used
Only where a Trimega hair-strand test for drugs or alcohol was prepared and an expert report submitted in your case (the form says during 2010 to 2014), and you say the result was wrong and materially affected your court order.
Before you start
- The final order, or the order directing the hair-strand testing, if you have it.
- The court that dealt with the case and the case number, if known.
- The children's full names and dates of birth.
- Names and addresses of the respondent and anyone else to be served.
How to fill in the C650
Open each part for what it asks and how to answer it. In Wren, each part is a few plain questions, and your answers fill in the form.
The test
You confirm a Trimega hair-strand test was prepared and reported in your case. If not, the form says not to complete it.
You, the children and the local authority
Your full name, the children's names and dates of birth and your relationship to them, and any local authority involved.
The original proceedings
The court and case number, whether you have attached the order, your role in the case and its outcome, and whether the test result was material to it.
What you are asking for
What you are asking the court to do and why, whether there is any reason the application should not be decided on paper or at a telephone hearing, and any later proceedings.
Service and signing
Who should be served, your address for documents, and the statement of truth, which you sign on paper.
Prepare your C650 with Wren Family
Wren Family turns official forms into short, plain-English questions you can answer at your own pace. You check everything before you send it: nothing goes to the court for you.
Get startedFree for 14 days, no card. Then £19.99 a month, with your money back within 14 days if it’s not right.
What happens after you send it
A judge may make an order on the information in the form without a hearing. Any party who objects can apply within 7 days for a hearing at which the application is reconsidered.
Common mistakes
- Using the form where the test was not carried out by Trimega Laboratories Limited.
- Sending other documents about the original case. The form says they will not be considered.
- Sending the form both by email and by post. The form says to use one or the other.
Common questions
Where do I send it?
The form gives an email address and a postal address on its last page. The email address uses an old government domain, so check GOV.UK or ask the court for the current contact details before sending.
Where these facts come from
These are the official rules and pages this page is based on. They are listed so you can check a detail for yourself; you do not need them to use Wren. They are outside Wren and open in a new tab.