Mario J. DeRossi

Mario J. DeRossi

also known as DeRossi Law Firm, LLC

4.9
Rating: 10.0

Licensed for 24 years

Divorce and separation Lawyer at Mineola, NY
Practice Areas: Divorce & Separation, Family, Child Custody, Child Support

100 Old Country Road, Suite 301, Mineola, NY

About Mario

Biography

Fees and Rates

We have not found any cost information for this lawyer


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Licenses

Licensed in New York for 24 years

State: New York

Acquired: 2001

Currently Registered

No misconduct found

Licensed in Massachusetts for 24 years

State: Massachusetts

Acquired: 2001

Inactive

No misconduct found

Location

DeRossi Law Firm LLC

100 Old Country Road, Suite 301, Mineola, NY, 11501

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Mario J. DeRossi's Reviews

Avvo Review Score

4.9 /5.0

113 Client Reviews

Showing 1 - 5 of 13 reviews | Family

Posted by anonymous | December 01, 2022 | Hired Attorney | Family

dishonest and careless

Mario represented me in family court over a period of over 2 years. While he comes across as confident and certain of himself, his work product is sloppy and harmful. Examples: -showing up to financial hearing without an FDA -telling me that it is fine to only pay what you can for child supp...ort, "the court will understand." This advice almost landed me in jail. -claiming to have done discovery of finances of the other party yet never sharing the product of that discovery, and not saving it in the files. when asked about this, he simply didn't answer. -accepting service of important papers on my behalf, without my consent, and not sharing them with me. I found out about them when I got the files back after letting him go, over a year after he accepted service. -the papers that he kept in my file was incomplete, like, less than half of what should be by law and by retainer agreement. -refusing to call out other lawyers and/or judges/magistrates for not following due process or for unethical behavior (something lawyers are ethically bound to do). -coercing me to sign a stipulation with so many holes in it that it is basically meaningless and almost unenforceable. it has cost me many thousands of dollars to attempt to rectify the stip he drew up last minute. -when he would give me one of his certain and authoritative answers or advice, and then later hearing him give the exact opposite advice, if I would call him out on this he would become extremely slippery and dishonest. In fact, he once told me with pride that he's "not a lawyer, but a liar." -submitting papers on my behalf without first letting me see what he was submitting. -failing to request counsel fees, multiple times, when I requested he do so. His response was "you seek counsel fees at any time." It's not that simple. At all. -He responded to emails quickly, but often in a way that showed he did not understand what was being asked, and did not make sure his own messages were clear and understandable. Often they were extremely vague, and he would simply not respond at all to certain questions, with no explanation of why. He'd just ghost them. -the list could go on a lot longer. The short message is, I absolutely would not recommend hiring Mario, unless you have enough money to flush down the toilet and care not about the issue you are hiring him for. If you care about your child, and are dealing with a mother that doesn't want their child to have a father, I do not recommend hiring him. I find all the 5 star ratings here very suspicious. If you read them, you'll see most of them write barely a sentence.

Posted by Michael | April 29, 2022 | Hired Attorney | Family

You will be in good hands.

I have had a fair amount of legal dealings in business and consider myself a relatively logical independent person. The dynamics of family law feel much different to me, there are emotions involved, decisions are complicated, compromise is often inevitable, and the results have a material impact on ...many lives. The best course of action is not always clear, it can be painful, it can be confusing, even to a logical and rational thinker. You need guidance from someone who understands and has a feel for the law. From my experience in the past year, Mario has a special talent for practical strategy and keeping things on course. All while respecting the factors that are most important to you. Mario always knows the answer, whether it be a technical legal question or more importantly, what to do at complicated decision points.

Posted by Jodie | January 04, 2022 | Hired Attorney | Family

I couldnt have done it with out him.

Look, divorces arent fun. Some people get lucky and have an amicable spouse and they can simply get divorced by signing a piece of paper and giving each other a hug and going on their merry way. I was not said, person. Mine was ugly, vicious, tough, heartbreaking, soul-destroying, and intense ...on a good day. When I tell you I would have been lost without Mario, I'm not exaggerating. He would calm me down when I was overreacting, he was present and available when i needed to be talked off that metaphorical ledge, he understood my grief and didn't try to belittle it. He was truly in my corner and I felt it every step of the way. I never had any doubt Mario was there for me, and had mine and my family's best interests at heart. He is sharp, funny, kind, but also understanding of how sensitive marital issues, especially with children are. If you are looking for an attorney that will go to bat for you, i hand on heart, can't recommend Mario enough. Mario, you know I think you are amazing, and I am forever thankful for getting me through one of the most trying times of my life.

Posted by anonymous | February 07, 2021 | Hired Attorney | Family

Powerful Representation

A divorce is usually one of the worst times of anyone's life. All through the ordeal, I felt that Mario had my back. I like his straight talk as I know that he will answer my questions honestly and always give me a realistic opinion. For the other side, Mario is a tough negotiator. As for me, his cli...ent, he was always available. It was never hard to get an answer from him, no matter how busy he was, he would always return my call the same day. Prior to hiring him, I had met up with several attorneys. However, I chose to go with him primarily because he was the best reviewed divorce attorney on AVVO. That proved out to be the correct decision, on my part. Moreover, he is equally outstanding in a family court setting. I think its important to have good legal representation as its noticed by the other side and it actually helps to expedite settlement and a speedy resolution of the case. At court, I have noticed first-hand, that he's very well respected by other attorneys as well as the judges and court clerks. All this matters. Also, Mario has an excellent team in place at his firm. I had a very good experience working with Nicole (associate attorney), Danielle (paralegal) and Ashley (assistant). Thank you all so much!

Posted by Pete | May 15, 2020 | Family

Divorce

My divorce was about the most chaotic, perplexing, insanely frustrating divorce in the history of divorces. Don’t take my word for it. Ask my attorney, Mario DeRossi. I’m sure, like me, it’s permanently etched in his memory. Mario DeRossi is just about the most professional, ethical attorney I hav...e ever had the pleasure of knowing....and I work in law enforcement so I know a few. The effort and painstaking diligence both he and his associate Nicole put into my case was jaw dropping. They were always available to answer my many incessant questions and handled my case EXACTLY the way I wanted it to be handled,. The way Mario conducted himself in court proceedings was especially impressive and not once, and this is a crucial component for anyone who has had to hire council, not ONCE did I feel like they were just trying to make a buck off my case. Mario DeRossi handled my case as if it were his own. I would, and have, recommended his services to anyone who is in unfortunately going through divorce, separation or family-related matters.

See All Client Reviews

Mario J. DeRossi's Lawyer Endorsements

Endorse Mario
Michael Robert Gionesi headshot
Michael Gionesi

Divorce and separation lawyer | Sep 17

Relationship: Fellow lawyer in community

"A powerful and zealous advocate for his clients, Mario has earned the respect of his peers and the judiciary. His level of civility is second to none, which makes him an even more effective advocate. His effectiveness is surpassed only by his keen intellect. I wholeheartedly endorse him."

Michael Drew DiFalco headshot
Michael DiFalco

Divorce and separation lawyer | Sep 19

Relationship: Opposing Counsel on matter

"I endorse this lawyer. Mario is an excellent attorney. We've had a couple of cases together and he's a zealous advocate for his clients while remaining a gentleman."

Somair Syed Alam headshot
Somair Alam

Divorce and separation lawyer | Feb 13

Relationship: Fellow lawyer in community

"Exceptional attorney, dedicated to client success. Highly recommended."

Joshua Bradley Hecht headshot
Joshua Hecht

Divorce and separation lawyer | Oct 02

Relationship: Fellow lawyer in community

"Mario is an exceptional attorney. His knowledge of family law matters is impressively extensive, but more importantly she has a deep focus on the needs of her clients. Highly recommended!"

Barry J. Gross headshot
Barry Gross

Divorce and separation lawyer | Jan 22

Relationship: Opposing Counsel on matter

"I endorse this lawyer. Mr. DeRossi is an extremely talented and knowledgeable attorney. He is "old school" in that his word is his bond."

Frederick William Vasselman headshot
Frederick Vasselman

Divorce and separation lawyer | May 29

Relationship: Worked for lawyer

"I endorse this lawyer."

Susan Ann Kassel headshot
Susan Kassel

Divorce and separation lawyer | May 17

Relationship: Opposing Counsel on matter

"I endorse this lawyer. Mario is always well prepared, clever and quick on his feet. He is an excellent attorney."

John M O'Brien headshot
John O'Brien

Commercial real estate lawyer | May 14

Relationship: Fellow lawyer in community

"A truly excellent attorney well respected in the legal community. I wholeheartedly recommend him to anyone looking for a lawyer who knows the law and truly cares about protecting the rights of his clients and getting them the most favorable result possible."

Christopher Daniel Leroi headshot
Christopher Leroi

Divorce and separation lawyer | Sep 15

Relationship: Fellow lawyer in community

"Mr. DeRossi is an outstanding attorney who provides exemplary advice on Avvo. I would recommend everyone and anyone to him for representation. Even though I have been practicing fo 24 years, as a judge, magistrate, prosecutors, and in private practice, I learn valuable new information from him every day. A superb attorney."

Howard M Lewis headshot
Howard Lewis

Divorce and separation lawyer | Jun 09

Relationship: Fellow lawyer in community

"I endorse this lawyer. Attorney DeRossi is an outstanding attorney with an exceptional reputation. He is a strong and zealous advocate for his clients and a credit to the legal profession. I highly recommend his legal services."

Ivan E. Young headshot
Ivan Young

Divorce and separation lawyer | Apr 10

Relationship: Fellow lawyer in community

"Having known Mario for a few years now, I can firmly state that he is a gifted attorney that advocates for his Client's in a manner rivaled by few. Not only does Mario have a profound knowledge of the law, but he truly is personable and attentive to his Clients which gives all those that go to him a genuine sense of comfort in such a stressful situation. I would and do recommend Mario to all Clients seeking representation in matrimonial related issues."

Jason Adam Isaacson headshot
Jason Isaacson

Divorce and separation lawyer | Oct 11

Relationship: Opposing Counsel on matter

"A strong advocate and always professional, Mr. DeRossi is an experienced attorney who offers practical solutions to resolve difficult issues."

Robert Scott Grossman headshot
Robert Grossman

Family lawyer | Jun 21

Relationship: Opposing Counsel on matter

"Mario and i were adversaries in a contested matrimonial case. I found him to be knowledgeable, a true professional, and most importantly, a man of his word."

Matthew Scott Seidner headshot
Matthew Seidner

Family lawyer | Mar 20

Relationship: Fellow lawyer in community

"Mr. DeRossi has an excellent reputation not only among other attorneys but before the bench. It is a privilege to consider him a colleague in an area of law that requires not only intelligence but compassion and patience."

Jill Altarac headshot
Jill Altarac

Divorce and separation lawyer | Nov 14

Relationship: Opposing Counsel on matter

"I have had several matters with Mr. DeRossi, and he is a strong advocate for his clients. Mr. DeRossi is very professional and works diligently to assist his clients achieve their intended results."

Caitlin Donahue headshot
Caitlin Donahue

Family lawyer | Aug 16

Relationship: Opposing Counsel on matter

"Mr. DeRossi displays an impressive level of professionalism and integrity while representing his clients. Not only does he have an obvious command of the law, but also places a high priority on maintaining the trust of opposing counsel."

Christian Aaron Pickney headshot
Christian Pickney

Divorce and separation lawyer | Aug 28

Relationship: Opposing Counsel on matter

"In a divorce case I handled against Mr. Derossi he represented his client zeaolously and professionally. He protected his client's rights and did not engage in unnecessary litigation that would have wasted our client's money and time. He knows the law and conducts himelf professionally. It was my privilege to work with this attorney."

Brian C. Pascale headshot
Brian Pascale

Personal injury lawyer | Aug 05

Relationship: Worked together on matter

"I endorse this lawyer's work. He is an amazing, detail oriented, and professional litigator."

Joseph DiBenedetto headshot
Joseph DiBenedetto

Divorce and separation lawyer | Apr 30

Relationship: Worked together on matter

"I endorse this lawyer's work. Mario is very competent and considerate of his client's needs. Mario has repeatedly obtained exceptional results for his clients."

View All Endorsements
Joseph Steven Dujmic Jr. headshot
Joseph Dujmic

Divorce and separation lawyer

Michael Robert Gionesi headshot
Michael Gionesi

Divorce and separation lawyer

Lawrence Bruce LaRaus headshot
Lawrence LaRaus

Divorce and separation lawyer

Michael Drew DiFalco headshot
Michael DiFalco

Divorce and separation lawyer

Joshua Bradley Hecht headshot
Joshua Hecht

Divorce and separation lawyer

Barry J. Gross headshot
Barry Gross

Divorce and separation lawyer

Frederick William Vasselman headshot
Frederick Vasselman

Divorce and separation lawyer

Howard M Lewis headshot
Howard Lewis

Divorce and separation lawyer

Karina Alomar headshot
Karina Alomar

Divorce and separation lawyer

Ivan E. Young headshot
Ivan Young

Foreclosure lawyer

Kenneth John Ready headshot
Kenneth Ready

Personal injury lawyer

Jason Adam Isaacson headshot
Jason Isaacson

Divorce and separation lawyer

Matthew Scott Seidner headshot
Matthew Seidner

Divorce and separation lawyer

Jill Altarac headshot
Jill Altarac

Divorce and separation lawyer

Caitlin Donahue headshot
Caitlin Donahue

Family lawyer

Christian Aaron Pickney headshot
Christian Pickney

Divorce and separation lawyer

Joseph DiBenedetto headshot
Joseph DiBenedetto

Criminal defense lawyer

Brian C. Pascale headshot
Brian Pascale

Personal injury lawyer

Experience

Rating:  10.0 (Superb)

Honors

2025

Super Lawyer, Super Lawyers

2024

Super Lawyer, Super Lawyers

2023

Super Lawyer, Super Lawyers

2022

Super Lawyer, Super Lawyers

2021

Super Lawyer, Super Lawyers

2020

Super Lawyer, Super Lawyers

2019

Super Lawyer, Super Lawyers

2018

Super Lawyer, Super Lawyers

2017

Super Lawyer, Super Lawyers

2016

Rising Star, Super Lawyers

2015

Rising Star, Super Lawyers

2014

Top 40 Under 40, The National Trial Lawyers

2014

2014 New York Metro Rising Stars, SuperLawyers

2014

Top Ten Ranking, The National Academy of Family Law Attorneys

2014

Top 40 Lawyer Under 40, The American Society of Legal Advocates

2014

Rising Star, Super Lawyers

2004

Award for Trial Advocacy, The Association of the Bar of the City of New York

2003

Army Commendation Medal, Trial Defense Service, United States Army

2003

Bronze Star Medal, Fourth Infantry Division, United States Army

2002

Army Commendation Medal, Fourth Infantry Division, United States Army

Work Experience

2009 - Present

Partner, Stern & DeRossi, LLP

2006 - 2009

Associate, Stern, Adler & Associates, LLP

2002 - 2006

Judge Advocate, United States Army

Associations

2014 - Present

The National Academy of Family Law Attorneys

Member

2014 - Present

The American Society of Legal Advocates

Me

2009 - Present

Nassau County Bar Association

Member

2009 - Present

New York State Bar Association, Family Law Section

Member

2009 - Present

Columbian Lawyers Association

Member

Education

2001

Saint John's University, School of Law

Juris Doctor

Languages

English

Activity

Avvo Rating

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Avvo Rating Levels
10.0 - 9.0 Superb8.9 - 8.0 Excellent7.9 - 7.0 Very Good6.9 - 6.0 Good5.9 - 5.0 Average4.9 - 4.0 Concern3.9 - 3.0 Caution2.9 - 2.0 Strong Caution1.9 - 1.0 Extreme Caution