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Dianne N Sullivan

Divorce and separation Attorney at Mesa, AZ

2.8   21 reviews
  • Licensed for 23 years
    State AZ
    Acquired 2000
    Status
    Active Lawyer disciplined by state licensing authority in 2017

About Dianne

Learn Dianne’s areas of practice.

3
Practice areas

Dianne N Sullivan is the managing attorney at Sullivan Law Office. Her practice includes divorce and family law representation.


Ms. Sullivan earned her B.A. in Social and Behavioral Sciences from Seton Hall University in South Orange, New Jersey, graduating cum laude with a minor in criminal justice. She received her law degree from the Arizona State University College of Law.

Early in her legal career, Ms. Sullivan was Assistant City Prosecutor with the Office of the Phoenix City Prosecutor and, thereafter, defense attorney with the Maricopa County Public Defender’s Office. At Sullivan Law Office, this very capable trial attorney handled all types of criminal law cases.


Arizona Divorce and Family Law
In family matters that are often intensely challenging and emotional for clients, Ms. Sullivan maintains the highest degree of professionalism in advocating on her clients’ behalf. Her cases include divorce, legal separation, annulment, child custody and parenting time, visitation, paternity establishment, complex property division, spousal maintenance, child support, custody modification and other post decree matters.


A spirited volunteer, Ms. Sullivan received the Pro Bono Services Award from Seton Hall University. In Arizona, she participates in the Volunteer Lawyers program which provides free legal services to qualifying individuals needing divorce and custody assistance, provides free estate planning for law enforcement and first responder personnel through the Wills for Heroes Program, and volunteers her time to assist veterans in need each year at the Veteran’s Stand Down.

Location

Sullivan Law Office
3707 E. Southern Avenue
Mesa, AZ, 85206
Sullivan Law Office
2375 E. Camelback Road
Suite 600
Phoenix, AZ, 85012
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Reviews

2.8 / 5.0
  21 customer reviews
Posted by Olga | June 29, 2021
This review is from a person who hired this attorney.
| Hired Attorney
Knowledgeable and Trustworthy
I hired Dianne as my divorce attorney. First of all, she is one of the very few attorneys who answers her phone and calls you back right away, I mean 6AM kind of right away:). She is very experienced, confident attorney with a lot of knowledge. She advised me on some details and worked by my side to protect my interests. She cares about her clients and by hiring her, I got an attorney whom I actually could trust. The feeling that I am protected and nothing was going to be missed made my stress levels lower and made me feel more confident during this stressful and emotional time. The case was settled; I have my house, my vehicle, and my kids - everything I asked for.
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Posted by anonymous | March 2, 2021
This review is from a person who hired this attorney.
| Hired Attorney
Caring and Wonderful Attorney
She's a wonderful attorney and she always listens to every single details. I am very grateful to have her as my attorney. She is very caring and knowledgeable. Thank you so much for how you have assisted me during my divorce case. I recommend my attorney Dianne to anyone for a family case.
Posted by Alexis | April 21, 2020
This review is from a person who hired this attorney.
| Hired Attorney
Lives up to her stellar reputation
I highly recommend the services of Ms. Sullivan as a competant, ethical and results driven attorney. From our initial meeting throughout the legal proceeding; Ms. Sullivan represented my best interests under the guidleines of the law and that of which we deemed fair and reasonable considerations. Her knowledge of the law and judicial process allowed me, a novice in divorce activity, to make proper decisions for my family; as well as, how those decisions would impact my future. Going through a legal process of any type is extreamely stressful. As is the case of divorce; compounded by emotions which can cloud proper judgement. Selecting an experieced lawyer can make the difference on how those decision impact the rest of your life. My case is now closed; but in reflection, I know the decisions made were seldom simple, but always 100% correct. I have Ms. Sullivan to thank for these results.
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Posted by Carmen | February 21, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Amazing attorney
I retained Dianne Sullivan a year ago for my Filter Law case. Dianne was the second attorney that I had retained in my on going Family Law case. Dianne was so understanding and on top of everything, that I was able to release her soon after my hearing date. Since that time, she has been there for me with any further questions or concerns that I have about issues that have arisen after the fact. If you want or need a knowledgeable Family Law attorney, Dianne Sullivan is my first choice and will be from here on out.
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Posted by anonymous | June 16, 2016
This review is from a person who hired this attorney.
| Hired Attorney
Case Dismissed!
Dianne represented me in a criminal case where I was unjustly charged with custodial interference. She lobbied hard on my behalf and got my case dismissed. Due to my profession, a conviction would have resulted in me losing my job. I could not be happier with her work on my case.
Posted by anonymous | June 12, 2016
This review is from a person who hired this attorney.
| Hired Attorney
Caring and Knowledgable
Hiring Dianne was the best decision I could have made in my divorce case. She truly cares about her clients, and worked hard to get me the best possible outcome. I've recommended her to several friends and family members, all who has similar experiences with her. Even her staff members are kind and know their stuff. I highly recommend her if you need someone experienced and no nonsense.
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Posted by anonymous | June 12, 2016
This review is from a person who hired this attorney.
| Hired Attorney
Great for victims of domestic violence
Dianne was a tremendous help to me in my case. I was a victim of years of domestic abuse, and no one seemed to take that seriously, especially the Court. At trial, Dianne fought hard for me and my son, and helped me win sole custody. If you're are looking for someone knowledgeable, who actually cares about you, and will fight hard, call Dianne.
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Posted by anonymous | August 23, 2014
Wonderful Experience!
I would recommend Dianne to anyone struggling with child custody issues. Dianne is aggressive, informed, and caring. Both Diane and her paralegal Marti were responsive and kept me in the loop, even though at times I probably seemed a bit over bearing. It takes a special kind of person to be a family law attorney, and Dianne is great.
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Posted by Yolanda | January 19, 2012
Dianne Sullivan great attorney
She helped me and my 6 month old son get through a domestic violence divorce and gave me the knowledge that I needed and help. I recommend her to anyone.
Posted by anonymous | October 2, 2014
vicious and money hungry.
diane was the most vicious and untrustworthy person I've ever met she drew by case out for more than a year bled my family dry destroyed my children and all she cared about was getting paid. if there's a way to go back and turn back the clock I would do it. And i wouldI do everything I could to keep Diane Sullivan away from my case
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Posted by Chris | May 29, 2024
This review is from a person who hired this attorney.
| Hired Attorney
Wouldn't give a 1 Star but Required
Has a "Badass Rep", she will act like she is tough & there to fight for you. That is a very overcharged ACT. She will definitely charge you a ton, and do NOTHING for the money. "Trial Fee", does not mean Trial either, and if you did do a trial & the doc then you would be in for 10,000 of thousands more for her to do little to nothing. If you want to pay an attorney to work hard for the other team, this is definitely your person. If you want to pay out the rear to ensure that you get treated like dirt, no communication, & even less empathy in a terrible situation, this is your person. If you want a manipulative human that only wants to demand what she believes, & not listen to what you want or what you desire & not stand up for you in anyway, this is your person. She is not at all timely with her responses, they can go for days or weeks without answer. She will not show for meetings that have been scheduled, and not give a reason. You will not be addressed until approximately 3 days before any of your trials or hearings, & then at that time you will be overwhelmed & rushed to get the information that is needed. Heaven help you if you don't have the additional funds, even if you have to sell your soul you better come up with the money, or else, her unqualified skills will become even less helpful to you. This lawyer ensured that walking through Hell was every bit of how it should be, the worst, and ensured you got absolutely nothing for your efforts in your family. Don't bother with the auto response, it would amount to anything anyway.
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Posted by anonymous | September 10, 2022
This review is from a person who hired this attorney.
| Hired Attorney
Hire someone who will work for YOU.
I hired Sullivan very briefly in my family law case, she never responded to my calls or emails about the case. The only correspondence I received is her attaching me to an email informing the opposing counsel(her friend I think), that I withdrew her counsel. Couldn't even walk in the office to address my case issues. Lack of communication, no effort to support my side of the case, and is more concerned with keeping her lawyer friends favoritism knowing she probably has to oppose against them once in while, its a court battle. Waste of time and money, recommend hire someone else. Thank you.
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Response from Dianne Sullivan May 7, 2024
Thank you for your comment. While I appreciate receiving reviews about my skills as a family law attorney, I feel it is unfortunate that you have elected to post a complaint on this website. Since you chose to post this review anonymously, it is difficult for me to comment or respond regarding any of the statements made in your review. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by anonymous | July 28, 2022
This review is from a person who hired this attorney.
| Hired Attorney
Terrible
Just don't waste your money. she will act like she is on top of things and going to do everything to help you when you first speak with her before she has your retainer in hand. Once she has that first retainer, you won't hear from her again, other than an email or two from her Paralegal, but never her. She will not call you back regardless of how important your message left for her is. And then without doing any work on your case, will request a SECOND retainer again. Keep in mind these retainers are $4000... and you're just left wondering, what happened to the first retainer I paid you? This "lawyer" is a joke and doesn't do the work you need even if she's paid well. Save your money for a GOOD family lawyer.
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Response from Dianne Sullivan May 7, 2024
Thank you for your comment. While I appreciate receiving reviews about my skills as a family law attorney, I feel it is unfortunate that you have elected to post a complaint on this website. Since you chose to post this review anonymously, it is difficult for me to comment or respond regarding any of the statements made in your review. As is noted in my firm's fee agreement, the firm bills my time at a reasonable hourly rate based upon the fact that I have been practicing family law for twenty four years. I does not appear from your review that you questioned or objected to your monthly statement of charges, which are provided by the firm. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by anonymous | March 16, 2022
This review is from a potential client who consulted with this attorney.
| Consulted Attorney
I'm glad I read these reviews
I'm a Father, and I would not hire you or spend a dime on you. So happy I read these reviews and you should be ashamed for the way you treat people, especially men.
Response from Dianne Sullivan May 7, 2024
Thank you for your comment. While I appreciate receiving reviews about my skills as a family law attorney, I feel it is unfortunate that you have elected to post a complaint on this website. Since you chose to post this review anonymously, and have never consulted with me, I am not in a position to comment any further. I wish you the best of luck in your matter.
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Posted by Daniel | October 16, 2021
This review is from a person who hired this attorney.
| Hired Attorney
Quit the day before trial for 2nd retainer
Diane accepted my case knowing I was homeless and covid era unemployed. I gave her every penny I had to make the retainer. Due to her negligence, my trial was postponed twice. Adding 3 months to her billable time. The day before trial she quit, citing I had not paid a 2nd retainer which included her "trial fee". We were one hour in court from reaching a decision. I was left to represent myself. When I told the judge I would proceed alone, he informed me there was no way to proceed because Ms. Sullivan had failed to enter a single piece of evidence or any exhibits that I had provided her on day 1 of our agreement for representation. She does not return phone calls or emails. I am still homeless thanks to Diane's lack of professional obligation. From the other reviews I would say if you are a woman, she may help you. If you are a man, she will bill you for every penny you have and do nothing in return. She should be be investigated thoroughly and will be if I have my say. Diane, save your prescripted heartless reply. You give the same answers to everyone.
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Response from Dianne Sullivan May 7, 2024
Thank you for your comment. While I appreciate receiving reviews about my skills as a family law attorney, I feel it is unfortunate that you have elected to post a complaint on this website. As is noted in my firm's fee agreement, the firm bills my time at a reasonable hourly rate, paid in advance of services, based upon the fact that I have been practicing family law for twenty four years. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by anonymous | May 23, 2021
This review is from a person who hired this attorney.
| Hired Attorney
Wouldn't even give it 1 star.
Whatever you do, DO NOT hire this lawyer. She is very money hungry and does not care about your case or you as a person whatsoever. She will continue to overcharge and overcharge you for literally nothing.
Response from Dianne Sullivan June 17, 2021
Thank you for your comment. While I appreciate receiving reviews about my skills as a family law attorney, I feel it is unfortunate that you have elected to post a complaint on this website. Since you chose to post this review anonymously, it is difficult for me to comment or respond regarding any of the statements made in your review. As is noted in my firm's fee agreement, the firm bills my time at a reasonable hourly rate based upon the fact that I have been practicing family law for twenty one years. I does not appear from your review that you did not question or objection to your bill, which is provided monthly by the firm. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by anonymous | November 27, 2019
This review is from a person who hired this attorney.
| Hired Attorney
DO NOT HIRE THIS ATTORNEY
I made the horrible mistake of hiring this so called attorney. She continued to charge me, while doing close to nothing. When we did go to court she was very unprofessional, she made several misstatements, the judge and the other attorney had to correct her. She did not listen to my wishes and pushed me to make agreements that were not in my child's best interest. Her legal documents are full of mistakes and she has even sent me other clients paperwork. I would not let my worst enemy hire this women.
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Response from Dianne Sullivan March 24, 2020
Thank you for your comment. While I appreciate receiving reviews about my skills as a family law attorney, I feel it is unfortunate that you have elected to post a complaint on this website. Since you chose to post this review anonymously, it is difficult for me to comment or respond regarding any of the statements made in your review. As is noted in my firm's fee agreement, the firm bills my time at a reasonable hourly rate based upon the fact that I have been practicing family law for twenty years. I does not appear from your review that you did not question or objection to your bill, which is provided monthly by the firm. Any agreement reached by parents regarding their children must contain, in order to be accepted by the Court, a statement that the agreement is in their children's best interest, as well as a statement that they were not coerced to make any agreements. I am extremely sorry for the way you felt you were treated. I recognize that when a client retains me, he or she is often going through one of the most difficult times in their lives, and I believe in complete honesty about what the client can expect during his/her family law matter. Sadly, when I deliver information to a client that he or she does not wish to hear or that he or she disagrees with, I take the risk that the client may not like my advice. I always strive to provide straightforward advice to my clients so they can make informed decisions about their case. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by Melissa | July 22, 2019
This review is from a person who hired this attorney.
| Hired Attorney
Overcharged did nothing!
Hired her for my divorce. Never even saw her for fear of what she kept charging me. Even if my ex called her she kept piling up the bill. I never even got to a full trial and it was 8k. I has to settle and have been miserable since. My ex is a narcissist psycho and was not properly represented. I have three kids and I am in a Mesa Az prison until they are 18. She never even tried to fight for me. It was all talk. And the spelling and wording on the decree wasn’t even proofread. I still cry over it 6 years later.
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Response from Dianne Sullivan July 23, 2019
Thank you for your comment. I feel it is unfortunate that you have elected to post a complaint on this website. As noted in the firm’s fee agreement, the firm bills my time at a reasonable hourly rate based upon the fact that I have been practicing family law for almost twenty years. Additionally, a client always has an opportunity to address any of his or her billing concerns with me, or the managing partner. I am extremely sorry that you are unhappy with the settlement you agreed to. I recognize that when a client retains me, he or she is often going through one of the most difficult times in their lives. I always strive to provide straightforward advice to my clients so they can make informed decisions about their case. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by anonymous | September 28, 2016
This review is from a person who hired this attorney.
| Hired Attorney
Complacent, Unprofessional and Untrustworthy
I hired Stewart Law to handle my divorce. I agreed to a settlement conference and my original attorney was on maternity leave so I was assigned to Ms. Sullivan. I emailed her before the conference to propose a discussion about strategy, how the conference works and the nature of the pro-tem judge, etc. I received no reply. One of her first acts was to go into a 'closed' briefing meeting with opposing counsel and the judge and to concede the one thing that gave me some financial leverage. However, she did not inform me of this until the end of a 9 hour day of negotiations. During the course of the day, she did nothing to argue or push back on ANY of the points the judge or opposing counsel threw at me. When I protested and asked her to help, she just shrugged her shoulders. As the afternoon wore on, she joked about it being 'martini time'. When I asked why my ex-wife needed the small fortune she demanded, Ms Sullivan said "she needs to get her hair done, and buy new shoes!" (there were no children involved in the divorce). When it got to the end of the day and the one item she, the judge and opposing counsel had agreed - to my significant disadvantage - I told her I did not agree. I repeatedly told her I would not sign the agreement and she argued with me for 20 minutes to sign it. I was placed under duress by her and the judge to sign a settlement agreement that I did not want to sign. It has caused me irreparable financial damage since. I spoke to the partner the next day, and it was clear they did not care about the quality of their work. I terminated my agreement with them and took my settlement agreement to another law firm to complete the divorce; they were astonished that I had exited a settlement conference with such an unfavorable agreement if I had a 'competent' lawyer present. I am sure that Ms Sullivan is a competent lawyer, but on this day she failed to fulfil her fiduciary duty to her client, she was complacent, unprofessional and unprepared and if I didn't know better I would say that she took the easy option and 'hung me out to dry'. I will be paying for it for the rest of my life.
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Response from Dianne Sullivan July 6, 2020
Thank you for your comment. I feel it is unfortunate that you have elected to post an anonymous complaint on this website. I am extremely sorry that you are unhappy with the settlement you agreed to so your matter could be finalized. I recognize that when a client retains me, he or she is often going through one of the most difficult times in their lives. I always strive to provide straightforward advice to my clients so they can make informed decisions about their case. Once again, I apologize if your experience did not meet with your expectations. I wish you the best.
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Posted by anonymous | July 26, 2015
Father's Beware
I found Dianne (Stewart and Lane) through my legal plan at work; one of two firms that was approved with the plan. I want to warn all father's out there that she is not the answer. She never once made an attempt to meet with me in person and would only do telephone conferences. After spending my entire savings to try and modify orders, she only got as far as temporary order so that I can see my son for 3 hours a day and every other Saturday. She showed no empathy for the ordeal that I was going through. She always made it feel like I was at fault, however if she would have just listened she would have known otherwise. I had to repeat several issues to her through email; she does not pay attention. I have a hard time believing she is even reading my emails. Save yourself a lot of time and money and seek help elsewhere. She does not care about helping anyone and only about receiving payment.
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AVVO RATING 9.1 (Superb)

Professional misconduct

This lawyer was disciplined by a state licensing authority in 2017.

Admonition and Probation issued in AZ, 2017
updated on 08/09/2020

An admonishment means the attorney did something wrong but may still practice law. While on probation, the State monitors the attorney's activities for a period of time in hopes that he or she will not repeat the behavior.

Dianne's comment: “An admonition is the lowest and most informal sanction the bar imposes. A former client who chose not to follow my advice was later sanctioned by the Court for her conduct. She filed a complaint, alleging I advised her to violate the Court's orders. While this allegation was not true, I should have withdrawn from the case rather than continue to advocate for this client and her children, and therefore chose to accept the bar's decision to issue an admonishion.”

Work Experience

  • Asistant Judge Pro Tem
  • Town of Litchfield Park
  • 2019 - Present
  • Judge Pro Tempore
  • City of Mesa
  • 2006 - Present
  • Managing partner
  • Sullivan Law Office PLLC
  • 2003 - Present
  • Associate Attorney
  • Stewart Law Group
  • 2013 - 2019
  • Assistant public defender
  • Maricopa County Office Of The Public Defenders
  • 2005 - 2007
  • Assistant City Prosecutor
  • City Of Phoenix Prosecutor's Office
  • 2001 - 2003
View all work experience

Education

  • Arizona state University
  • JD - Juris Doctor
  • 2000
  • Seton Hall University
  • BA - Bachelor of Arts
  • 1997
  • Belleville High School
  • High School Diploma
  • 1993

Associations

  • State Bar of Arizona
  • Member, Bench and Bar Committee
  • 2019 - Present
  • Mesa Chamber of Commerce
  • Member
  • 2018 - Present
  • Association of Family and Conciliation Courts
  • Member
  • 2013 - Present
  • Maricopa County Bar Association, Family Law Section
  • Member
  • 2012 - Present
  • State Bar of Arizona, Family Law Section
  • Member
  • 2012 - Present
  • Arizona Attorneys for Criminal Justice
  • Member
  • 2004 - Present
  • National Association of Criminal Defense Lawyers
  • Member
  • 2004 - Present
View all associations

Languages Spoken

  • English

Honors and Awards

  • 10 Best Attorney
  • American Institute of Legal Counsel
  • 2018
  • Top 10 Attorney
  • National Academy of Family Law Attorneys
  • 2018
  • Avvo Top Rated Lawyer
  • Avvo
  • 2018
  • Top 100 Trial Lawyers
  • The National Trial Lawyers
  • 2017
  • Pro Bono Services Award
  • Seton Hall University
  • 1997
View all awards

Attorney endorsements

Received (12)
Given (5)
Endorse Dianne
Family Attorney | Sep 10
Relationship: Opposing Counsel on matter
"I endorse this Dianne. She is a very diligent and zealous advocate for her clients. We had a very difficult relocation case adverse to one another. Dianne was very professional, prepared and extremely knowledgeable on complex family law issues."
Divorce and separation Attorney | Jul 19
Relationship: Opposing Counsel on matter
"I have had the opportunity to work with Dianne as opposing counsel and her work ethic, follow through, and knowledge of the law are second to none. Dianne has a wonderful and respected presence in the courtroom, and is effectively able to convey her client's position."
Divorce and separation Attorney | May 26
Relationship: Co-worker
"Dianne is an excellent lawyer and a caring individual. I strongly recommend her."
Family Attorney | Oct 08
Relationship: Opposing Counsel on matter
"Over the course of many years, Dianne and I have worked together as opposing counsel on various cases. She is an assertive advocate for her clients and a worthy opponent. What I like best about Dianne is that she "tells it like it is" without pulling any punches. Dianne is a creative and sharp attorney. I endorse her."
Criminal defense Attorney | Jun 14
Relationship: Fellow lawyer in community
"Dianne is a great attorney and a terrific person. I always see her in the courthouse hallways taking the time to really speak with her clients. I know she does a great job for them. I endorse this lawyer."
Family Attorney | Oct 22
Relationship: Fellow lawyer in community
"I endorse this lawyer."
Family Attorney | Sep 27
Relationship: Fellow lawyer in community
"Dianne is an outstanding attorney who brings level of professionalism and personal attention to each of her clients. I highly recommend her."
Family Attorney | Jul 28
Relationship: Fellow lawyer in community
"I have known Ms. Sullivan for several years and have personally observed her in court. She is an excellent attorney that obtains great results for her clients. I endorse this lawyer."
Criminal defense Attorney | Jul 19
Relationship: Fellow lawyer in community
"I endorse this lawyer. Ms. Sullivan is an agressive advocate for her clients and very capable trial attorney."
Criminal defense Attorney | Feb 01
Relationship: Opposing Counsel on matter
"I endorse this lawyer."
Family Attorney | Jan 10
Relationship: Fellow lawyer in community
"I endorse this lawyer. Dianne Sullivan is an excellent attorney who fights hard for every one of her clients. She has a wealth of knowledge and uses every bit of it to help her clients."
Family Attorney | Jan 10
Relationship: Opposing Counsel on matter
"I endorse this lawyer. Dianne Sullivan is aggresive, highly competent & well-versed in the law. I have worked with Dianne on several family matters, all of which were complex in nature as well as highly emotional and difficult for the clients. She was able to aggresively advocate while maintaing the highest level of professionalism and integrity."
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