Mark established O'Sullivan Kenny with Matthew in 2016 and was previously a partner in a leading Criminal Defence Firm.

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He previously worked in two leading criminal law firms before setting up his own firm in 2012.  He has continued to specialise in criminal law and related areas since then.

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Mark has represented clients in all Courts from the District Court to the Supreme Court.

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He has extensive experience in the preparation of trials for both the Circuit Criminal Court and the Central Criminal Court.

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He is also highly experienced in advising detainees in Garda Stations.

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He has successfully brought judicial review and habeas corpus proceedings on behalf of clients in the High Court.

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Mark appears daily in the District Court where he represents clients charged with all criminal and road traffic offences.

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What our clients say about Mark:
 

"Let me to take this opportunity to say special thank you to "Mark O'Sullivan" for helping me in a very decent and professional way.
I am so inspired by your highly civilized and professional way of communication. I have been going through extreme stress before I spoke to you but I have to say that I contacted you at the right time. You listened patiently and explained the pros and cons of the matter in a very simple but professional way and it made me feel that there is someone who understands and is willing to help me. I would highly recommend you to anyone looking for legal advice.
Talking to you worked like free counseling for me.
Thank you again for providing me with best professional services."

S.A.

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"Mark was great help in my case, very professional and extremely capable. Thank you for your assistance."

M.F.

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"After a four year period of complete uncertainty, today I was given my freedom, thank you to the whole legal team at O Sullivan Kenny solicitors , completely unexpected by both myself and my wife , I would 1,000% suggest this law firm as your legal representation as I believe in my own heart and soul there is no better team to give you a fighting chance moving forward, Thank you Mark for all you have done and especially to the rest of your team!"

D.H.

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"I have first meeting with Mark O'Sullivan of O'Sullivan Kenny LLP and I am very impressed with his professionalism and how quick he have responded to me. I feel very happy so far and very thankful to have him as my solicitor".

A.N.