Employment: Employer
London (Firms)
2 years ranked
LAWYER PROFILE
John Hayes
UK 2026
Ranked in 1 practice area
Contributions and articles
4 Articles, Press releases, highlights
About
Provided by Constantine Law
UK
Practice Areas
John Hayes is the Founder and Managing Partner of Constantine Law.
John advises UK corporates on their employment law issues in the financial services, recruitment, tech and construction sectors. John has particular expertise in restrictive covenant disputes; he is an experienced High Court practitioner and has obtained numerous injunctions for a range of leading corporate clients, in the High Court, in recent years.
John advises senior executives requiring high-level employment advice on a wide range of issues. He has years of experience litigating in the Employment Tribunal, and the Employment Appeal Tribunal in unfair dismissal, whistleblowing and equal opportunities cases.
John is also highly sought after for his experience in the arena of a-typical working, including consultancy agreements, IR35, CIS and the tax implications of each.
Career
John Hayes founded Constantine Law in 2015. Prior to this he headed the employment department of a large, national law firm.
John qualified as a barrister in 1993 and as a solicitor in 2001.
Chambers Review
Provided by Chambers
Chambers Guide to the Legal Profession
Employment: Employer - London (Firms)
Band 5
Individual Editorial
John Hayes is the founder and partner at Constantine Law. He has experience handling various employment matters including on behalf of senior executives.
Strengths
Provided by Chambers
He is a wonderful person to have in your corner and I think genuinely cares about securing outcomes for his clients.
Employment: EmployerChambers Guide to the Legal ProfessionJohn Hayes has been outstanding throughout. His leadership, clarity and attention to both detail and big-picture strategy are consistently impressive.
Employment: EmployerChambers Guide to the Legal ProfessionJohn was fantastic.
Employment: EmployerChambers Guide to the Legal ProfessionJohn Hayes is very commercial, handles clients very well and gives them confidence. He always goes out to bat for the client and is very good with them.
Employment: EmployerChambers Guide to the Legal Profession
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UK-wide
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Professional Discipline
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Articles, Highlights and Press Releases
4 items provided by Constantine Law
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