Sean Dennis Hennessey

PRO

Sean Dennis Hennessey

5.0
Rating: 10.0

Licensed for 34 years

Criminal defense Lawyer at Westminster, CA
Practice Areas: Criminal Defense, Personal Injury, Civil Rights, Juvenile

8231 Westminster Blvd, Westminster, CA

About Sean

Biography

For 23 years I have been a trial lawyer practicing personal injury and criminal defense cases.

Practice Areas

4

Practice Areas

Criminal Defense 40%

I have handled all types of criminal cases from murders, sexual crimes, gang crimes, third strike cases down to less serious crimes like petty theft or vandalism. I represent both adults and juveniles charged with crimes. I was a former Senior OC Public Defender where I spent 9 1/2 years handling only serious felony cases. I have represented 1000's of clients and tried 100's of cases. I am very well known by prosecutors as being an aggressive, prepared attorney who fights for every client.

35 years | 2,000 cases

40%
Personal Injury 30%

Personal injury cases cover a wide variety of cases including car collisions, medical malpractice cases, slip and fall incidents, dog bites, assaults, batteries, or injuries from defective products. Generally any times one person or entities actions injure another person a personal injury case can result. Each case must be thoroughly reviewed and analyzed by an experienced personal injury lawyer to determine who may be at fault and the various causes of actions which may result from any injury.

24 years | 150 cases

30%
Civil Rights 20%

The types of civil rights cases my law firm handles typically involve people who have been injured by members of law enforcement either during street encounters, inside a police station, incidents that occur inside a jail or prison, high speed pursuits, during the service of search warrants or during the many other times a member of law enforcement, firefighters, paramedics or others involved with or associated with law enforcement agencies ultimately injure a member of the public.

24 years | 50 cases

20%
Juvenile Law 10%

The Juvenile cases I handle are "Dependency cases". These are cases where a Social Services Agency ("SSA") either takes a minor child from their family home or threaten to do so. I represent one of the parents of the children removed by a SSA. SSA agencies have extraordinary powers to remove children based upon little or no evidence. SSA's decisions to "shoot first and usually ask no questions later" are often upheld by the Court's; thereby making the Dependency courts the scariest in California

22 years | 500 cases

10%

Fees and Rates

Cost

Contingency

30%-40%

Retainer

Sometimes


Payment Methods

  • Cash
  • Check

Awards

Client's Choice
Client's Choice
2014

Licenses

Licensed in California for 34 years

State: California

Acquired: 1991

Active

No misconduct found

Location

Law Offices of Sean Dennis Hennessey

8231 Westminster Blvd, Westminster, CA, 92683

hennesseytriallawyer.com

Sean Dennis Hennessey's Reviews

Avvo Review Score

5.0 /5.0

11 Client Reviews

Filter Avvo Reviews (11) Refine reviews to match your needs. Use the filters to quickly surface reviews that align with your case or priorities.

Showing 1 - 3 of 3 reviews | Practice Area Knowledge

Posted by anonymous | June 05, 2016 | Hired Attorney | Criminal Defense

When no one else listened!

My case was plagued with lots of police misconduct and violation of my rights. Every attorney I got was "ready" to fight or so they said until they got the retainer. All my previous attorneys wanted me to settle for ridiculous plea deals. Sean was the only attorney that was able to uncover 2 differen...t police reports for my case and brought to light all the things the police lied about to get the case to stick. Sean is like a pit bull in the court room with still being beyond professional. If your case has a lot of issues or you simply just want someone that will actually be thorough and do what they say, get Sean.

Posted by Kevin H. | February 16, 2014 | Criminal Defense

Excellent lawyer

Mr. Hennessey represented me on two different serious cases. On both cases I was facing more than 20 years on each case. On each case Mr. Hennessey fought the police and the District Attorney’s Office. On the first case where I was facing multiple strike felonies, gang crimes and was being o...ffered between 10-20 years. Ultimately the case settled for a non-strike felony after Mr. Hennessey cross examined the gang officers for over two days. The gang charge was ultimately dismissed by the District Attorney’s Office. The Judge during that case yelled at the gang officer because he would not answer any of the questions Mr. Hennessey was asking. On the second case I was again charged with multiple strike felonies cases and was facing a minimum sentence of 15 years. Mr. Hennessey conducted a thorough investigation and proved that most of the allegations were made up by the alleged victims. Mr. Hennessey was able to negotiate the case down to a misdemeanor and I was given credit for time served. I would highly recommend Mr. Hennessey. He is an extremely knowledgeable criminal defense lawyer and is very knowledgeable about gangs and the gang laws. Also Mr. Hennessey is able to cross examine police officers and point out to the Court the police are not being truthful. Kevin H.

Posted by John | January 09, 2014 | Probate

Genuine and caring.

I was referred to Sean from another attorney. However, Sean was not an expert in probate law and ultimately could not take my case. However, he has some knowledge about the area of of probate law and spent about 20 minutes on the phone with me in providing me with what he thinks are the next steps to... take and where I can find a good attorney to help me with my case. He did not referred any specific attorney, therefore he did not benefit from any referral fees. Even within my 20 minutes conversation with Sean, I could tell that he would be someone I want on my side who cares about the case and the people involved. He also worked at the public defender office for a while, which is highly commendable because it shows that he cares about less privileged individuals. I would recommend Sean.

See All Client Reviews

Sean Dennis Hennessey's Lawyer Endorsements

Endorse Sean
Paul J. Molinaro headshot
Paul Molinaro

Civil rights lawyer | Sep 15

Relationship: Other

"I endorse this lawyer."

Michael S. Waddington headshot
Michael Waddington

Criminal defense lawyer | Jun 04

Relationship: Fellow lawyer in community

"I endorse Sean. He is a highly skilled attorney that is well respected in the legal community."

Alan Castillo headshot
Alan Castillo

Criminal defense lawyer | Feb 21

Relationship: Worked together on matter

"I have known Sean Hennessey for well over 15 years. Simply put, one of the best cross-examiners that I have ever met in my 20 years of practice as a Lawyer. Sean is a skilled criminal defense and personal injury lawyer. More importantly, he cares about his clients and is committed to fighting for their cause. The fact is he is relentless and an outstanding advocate. I highly recommend Attorney Sean Hennessey."

Mark Stuart Devore headshot
Mark Devore

Criminal defense lawyer | Feb 19

Relationship: Worked together on matter

"I have known Sean professionally for nearly 20 years. IMO he is probably the best cross-examiner in Orange County. Whether civil or criminal his preparation is always top notch and his questioning tenacious. If you have to go trial criminally or have a tough civil case where the defense is a well-funded corporation or government entity, Sean is definitely a lawyer you consider."

Jennifer Ann Holden headshot
Jennifer Holden

Criminal defense lawyer | Feb 19

Relationship: Fellow lawyer in community

"I endorse this lawyer. I worked with Sean on a felony trial several years ago resulting in a not guilty verdict. He is a skilled trial lawyer and is passionate about his client."

Vincent John LaBarbera Jr headshot
Vincent LaBarbera

Criminal defense lawyer | Feb 19

Relationship: Worked together on matter

"Sean is a zealous advocate and skilled trial lawyer. I first met Sean over fifteen years ago - we successfully defended two young clients accused of attempted murder. Both clients were exonerated at trial - the jury found them not guilty. I would not hesitate to work with him again."

John Anthony Mango headshot
John Mango

Personal injury lawyer | Feb 18

Relationship: Fellow lawyer in community

"I've known Sean for close to 10 years and witnessed his work both first hand and through word of mouth of trusted attorney colleagues. Based on this experience, I feel one hundred percent confident giving him the highest endorsement possible. In fact, I've received a few civil litigation referrals over the years from friends and family. These are important cases because they involve people I care about. Civil cases are beyond the scope of my expertise, and the one and only attorney that I trust to refer these cases to is Sean Hennessey. He is a tireless advocate for his clients. He always seems to have the right answer at his fingertips. Let me put it this way, if I personally needed an attorney, Sean Hennessey would be my guy."

Kirra Leland O'Toole headshot
Kirra O'Toole

Criminal defense lawyer | Feb 18

Relationship: Fellow lawyer in community

"I strongly endorse this lawyer. He is an excellent trial attorney and will go to great lengths to ensure his clients get the best representation possible."

Paul Thomas Dequattro headshot
Paul Dequattro

Juvenile law lawyer | Feb 17

Relationship: Worked together on matter

"I have over 38 years of lawyering experience. Over a 15 year span, I’ve worked with, and observed Mr. Hennessey in numerous juvenile cases, and criminal cases, including reading transcripts of his trials. If any member of my family should ever need a lawyer in a criminal or juvenile setting, Mr. Hennessey would be my first choice for representation. His litigation instincts, particularly his cross-examination skills, are amongst the best in Orange County."

Case Christopher Barnett headshot
Case Barnett

General practice lawyer | Feb 16

Relationship: Worked together on matter

"I have worked with Sean on various matters over the last several years and there is no lawyer in Southern California who fights harder for his clients than Sean. He is fearless in his representation and backs down from no one. He is a skilled trial lawyer who understands the nuances of being in front of a jury. I endorse Sean wholeheartedly."

View All Endorsements
Mark Stuart Devore headshot
Mark Devore

Appeals lawyer

Kevin Jeffrey Phillips headshot
Kevin Phillips

Appeals lawyer

Alan Castillo headshot
Alan Castillo

Criminal defense lawyer

Kenneth Armand Norelli headshot
Kenneth Norelli

Criminal defense lawyer

Vincent John LaBarbera Jr headshot
Vincent LaBarbera

Criminal defense lawyer

Liem H. Do headshot
Liem Do

Personal injury lawyer

John Anthony Mango headshot
John Mango

Criminal defense lawyer

Bryan Joel Harris headshot
Bryan Harris

Criminal defense lawyer

Paul Thomas Dequattro headshot
Paul Dequattro

Juvenile law lawyer

Case Christopher Barnett headshot
Case Barnett

Criminal defense lawyer

Kirra Leland O'Toole headshot
Kirra O'Toole

Criminal defense lawyer

Experience

Rating:  10.0 (Superb)

Honors

2020

Super Lawyer, Super Lawyers

2019

Super Lawyer, Super Lawyers

2018

Super Lawyer, Super Lawyers

2017

Super Lawyer, SuperLawyers

2016

Super Lawyer, SuperLawyers

2015

Super Lawyer, SuperLawyers

2014

Top criminal defense lawyers, Southern California Super Lawyers

2014

Top Attorneys, Orange Coast Magazine

2014

Super Lawyer, SuperLawyers

2012

Super Lawyer, Super Lawyers

2012

2012 Best Hard Charging Lawyer, OC Weekly

2011

Super Lawyer, Super Lawyers

2010

Super Lawyer, Super Lawyers

2009

Super Lawyer, Super Lawyers

2008

Super Lawyer, Super Lawyers

2007

Super Lawyer, Super Lawyers

2006

Super Lawyer, Super Lawyers

Work Experience

2006 - Present

Owner, The Law Office of Sean Hennessey

1995 - 2006

Senior Deputy Public Defender, Orange County Public Defender's Office

1991 - 1995

Associate, Law Office of Marc Stern

Associations

2014 - Present

Martindale Hubbel

Member

2012 - Present

Litigation Counsel of America

Fellow

Education

1991

University of San Diego School of Law

JD - Juris Doctor

1987

Ohio Wesleyan University

BA - Bachelor of Arts

Languages

English

Activity

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