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O'Neil G Dennis

Family Attorney at Oakland, CA

4.4   7 reviews
Free consultation Virtual consultation available
Free consultation Virtual consultation available
  • Licensed for 15 years
    State CA
    Acquired 2008
    Active No misconduct found

We have not found any instances of professional misconduct for this lawyer.

About O'Neil

Learn O'Neil’s areas of practice.


O'Neil Law Firm is a respected law firm advocating for clients in Environmental Law, Family Law and Adoption cases. Based in Oakland, we are familiar with the courts of the Oakland area throughout all of California. Our attorneys have the necessary skill to help you resolve your legal problem. No matter what your case involves, we are focused on your success. Please read our profiles to learn more about our professional backgrounds.

Knowledgeable attorneys handle multiple areas of the law
O'Neil Law Firm has a thorough understanding of California law. Our lawyers work hard to help you get the best possible results in the following practice areas:

Environmental Law: Due to the complexity of environmental laws, it is important for businesses to be represented by attorneys who are familiar with the law. Our lawyers have significant experience in environmental law and have the skills necessary to successfully guide you through the legal process.

Family Law: Changes in your family structure pose many challenges. Whether you are pursuing adoption, experiencing marital conflict, or facing another issue close to home, you need a family law attorney who can help you find solutions for your legal problems. We answer all of your questions as we guide you through your family law matter.

Adoption: Adopting a child should be a joyous occasion for your family. However, the process can be complicated and frustrating. Our experienced attorneys help clients through the adoption process, bringing your child home as soon as possible.

Child Support: When parents go through a divorce, they have to decide how to best support their children. At our firm, our goal is to protect your children’s right to financial security. Our experienced attorneys are here for you during your child support case.

Divorce: Choosing to dissolve your marriage can be stressful and overwhelming. There are many decisions you have to make, such as child custody and spousal support. During your divorce, you need an experienced attorney to advocate for the best interests of you and your family. Our lawyers are dedicated to helping you through the divorce process.

Obtaining Domestic Violence Orders: At our firm, our experienced attorneys provide skilled representation to clients seeking orders of protection. We can help you seek a restraining order to protect you and your family.

Defending Against Domestic Violence Orders: At our firm, our experienced attorneys provide skilled representation to clients fighting to avoid restraining orders. We help defend your rights when you are facing the prospect of arestraining order.

Child Custody: When you are going through a divorce, the well-being of your children is always a top priority. Our attorneys have significant experience in all aspects of child custody law. We are dedicated to protecting your right to raise your child in a healthy environment.

When you retain the services of O'Neil Law Firm, you can be assured that your attorney is fully qualified to take on your case.

Contact our reputable California law firm today
O'Neil Law Firm sees your case through from start to finish. Let our lawyers work with you to address your legal concerns. Our office is conveniently located in Oakland. Call our firm at to arrange your free consultation or contact the firm online.


Top Contributor 2012
Top Contributor


O'Neil Law Firm, Inc.
O'Neil Law Firm, Inc.
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4.4 / 5.0
  7 customer reviews
5 Star
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1 Star
Posted by Teresa | October 27, 2022
This review is from a person who hired this attorney.
| Hired Attorney
Mr. Dennis doesn't miss a beat. I wish I could have hired him for everything. In a short time he made all the difference for me in a dirty divorce. I am still dealing with a disgruntled ex and as i go thru the work Mr. Dennis did several years ago, I looked for a page online where I could give him the review he deserves! He knows what he is doing. He is well spoken and fights for you. He is supposed to be an attorney! It's hard to find one like him!
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Posted by Justin | March 31, 2021
This review is from a person who hired this attorney.
| Hired Attorney
Professional , Dependable, This is who you want!!
I believe my custody case is an uphill battle. Being long distant from the county for court. O'Neil Dennis is making everything so easy. The filings are prompt & professional. He is going above and beyond my expectations as a first time client. Trust me if you need an attorney contact O'Neil first.
Posted by Donna | November 15, 2016
This review is from a person who hired this attorney.
| Hired Attorney
Goes above and beyond
He is an awesome Atty... He goes above and beyond to help his clients... He will follow every lead and every avenue he can to help your case... He truly cares
Posted by Anne | December 19, 2013
Highly Recommended
O'Neil Dennis is an outstanding professional. I engaged him to represent me in family court on the basis of his reputation for being prompt, thorough, prepared, experienced and candid. Mr. Dennis took my child custody case on short notice and worked late into the evenings with me in order to be prepared for my court date. He responded to my phone calls, answered all of my questions and made sure that I clearly understood what the outcomes may be. Most importantly, he made me feel comfortable in the court room. I would highly recommend O'Neil Dennis, and he will be my first phone call if I need representation again.
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Posted by anonymous | December 31, 2010
Assisted with a birth father termination
O'Neil went above and beyond in this case. Not only did he get the termination done quickly, but he was able to assist with obtaining aap, a difficult task in a private adoption. His fees were very reasonable and I found him to be very personable and reliable. O'Neil is knowledgeable and willing to research possible strategies that other attorneys wouldn't. I would recommend him to anyone needing a lawyer in the family law arena.
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Posted by anonymous | May 29, 2010
Excellent Asset to any case!
Very in touch with client needs, and extremely knowledgeable. I feel very safe and confident in having this attorney on my side.
Posted by Mark | December 12, 2013
Lacks knowledge of family law/divorce, scary.
I consulted this lawyer for my FL case. I found my settlement said I had a long term marriage, would need to pay ex $4,000/mo. if she remarried, and a horribly large amount of alimony, not based on a dissomaster. I found myself about to retire on $2,000/mo., ex had stolen retirement, and business was falling. Mr. Dennis told me everything was set in stone and could not be changed!!! He said nothing could be done! I found a great atty, Mr. [redacted} (voted Chico's best) who is changing it and said it could be changed. I actually had a short term marriage, my ex was still not working, is a hairdresser and I've been her social security, standard is no alimony if ex remarries, etc. This guy is scary with lack of knowledge/assertiveness.
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  • Free Consultation 30 minutes
Payment methods
Cash, Check


AVVO RATING 7.2 (Very Good)


  • Alameda County Bar Association
  • Family Law Referral Panelist
  • 2016 - Present
  • Contra Costa County Bar Association
  • Family Law Referral Panelist
  • 2016 - Present
  • San Francisco Bar Association
  • Family Law and Contempt Referral Panelist
  • 2011 - 2016

Languages Spoken

  • English

Attorney endorsements

Received (6)
Given (2)
Endorse O'Neil
Family Attorney | Apr 07
Relationship: Fellow lawyer in community
"I endorse this lawyer."
Family Attorney | Mar 03
Relationship: Fellow lawyer in community
"I endorse this lawyer. Mr. Dennis is a very knowledgeable attorney who works hard for his clients."
Family Attorney | Oct 07
Relationship: Fellow lawyer in community
"I endorse this lawyer. I am pleased to witness O'neil G Dennis' ability to handle complicated cases with care and determination to provide the best possible results for his clients."
Family Attorney | Jan 19
Relationship: Fellow lawyer in community
"Mr. Dennis is an excellent family law attorney. I routinely refer those with family law issues his way. He is extremely dependable, detail-oriented and obtains great results."
Family Attorney | Mar 05
Relationship: Fellow lawyer in community
"I endorse Mr. Dennis. He has quickly established himself as a well respected attorney in Butte County."
Family Attorney | Jan 07
Relationship: Fellow lawyer in community
"I endorse this lawyer. Very professional and very knowledgeable."
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Criminal defense
Oakland Family Lawyer O'Neil G Dennis
O'Neil G Dennis
Family Attorney
Oakland, CA
Licensed for 15 years
Free Consultation
Virtual consultation available