Mark established O'Sullivan Kenny with Matthew in 2016.  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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Along with his colleague Matthew Kenny and barrister Oisin Clarke BL, Mark updated a leading text book on road traffic law - Woods on 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.