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Blackstone Investigations Group, LLC (BIG.)

Blackstone Investigations Group, LLC of Mount Laurel, New Jersey offers premier private investigation services across the entire state of New Jersey. Our agency of professional and discreet private investigators provide investigative and surveillance services for private clients, corporate clients, law firms and attorneys. We have years of experience handling a variety of sensitive cases, including cohabitation and alimony, infidelity/cheating spouses, child custody cases, workers comp and insurance fraud investigations and personal injury cases. At Blackstone Investigations Group, LLC our teams of experienced investigators provide quick, effective, and confidential solutions to uncover the information you need in a timely manner. The office is open 24/7 so don’t hesitate to call us now. Feel free to check out the entire site to learn more about the owner and the services we provide. CALL US TODAY !

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All Blackstone Investigations Group LLC private investigators and subcontractors are fully trained, licensed, and in compliance with local, state, and federal laws to ensure our clients receive the highest quality services.

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  • My wife and I have 3 teenage children, 2 boys and 1 girl, all are very close. A few months ago, we noticed that our daughter began acting strangely toward her brothers and my wife and I, her schoolwork was slacking, and she became more distant as the weeks went by. We all knew something was different but didn’t know exactly what was going on. Our friends recommended we hire Dave to do surveillance on our daughter to monitor her activities after school, so we did. Within 48 hours, Dave determined our daughter was leaving school early with two friends and smoking marijuana in the woods before coming home. To most people, this is not an earth-shattering event, but for us, it was some more information than we had before, and we now at least had an explanation for our daughters’ actions. Never be fearful of doing what you need to do to protect your kids! Thank you, Dave.

    - BOB H. 12-22-22 MOORESTOWN, NJ

  • I hired Blackstone Investigations to conduct an online in-depth background check and to do surveillance on my fiancé whom I suspected of having a lengthy criminal background, even though he strongly denied having any past issues. The background check instantly revealed an extensive criminal history and arrest record and surveillance showed he was hanging out with his old drug users from his old neighborhood in Newark, NJ. So thankful I did this. Thank you, Dave, for such a great service.

    - KAREN E. 11-1-22 MONTCLAIR, NJ

  • Dear David, I am writing you this “Thank you” card after going through one of the most difficult times in my life, a time that I know you too have been through before. As you know, I was married to the love of my life for many years and together we have two beautiful children. But when things began feeling off in the relationship, I knew something was wrong. Contacting your office was the hardest but the smartest phone call I have ever made. I didn’t want to spend the money to prove something I already knew was going on, but I had to do something about it so I knew I wasn’t going crazy. And I’m glad I did! The amount of patience, understanding and compassion you showed towards me went above and beyond, and for that I am eternally grateful.

    - BONNIE R. 10-14-22 CLIFTON, NJ

  • After finalizing my divorce last year, I retained Dave’s services to locate my ex-husband and his assets after he skipped town to avoid his legal and financial responsibilities. Dave not only found my ex-husband, but was able to locate many of my ex-husband’s well hidden assets. Upon request from my attorney, Dave was also able to locate current banking information as well. This was the break in the case I so desperately needed! Thanks Dave

    - DONNA B. 9-12-22 SOMERS POINT

  • Dear Dave, as you know, dealing with children in difficult and unsafe situations is always a challenge. So, when I contacted you and explained the difficult details surrounding my young twin girls while having shared custody time with their father, you embraced the situation and promised to do your best. After weeks of surveillance, you were able to uncover many facts which proved helpful in my custody case. Thanks so much for your assistance. It made all the difference in the world for my custody battle!

    - MARTY R. 8-8-22 LUMBERTON, NJ

  • To Blackstone, there aren’t many professional forensic analysis folks in the area, but you and your partner Mike M. are some of the best I’ve ever worked with. Your level of knowledge, expertise and true professionalism was second to none and I would highly recommend your services to anyone who needs to recover data from their electronic devices. Thanks again Dave.


  • To Dave and the Team, it took all my strength to get enough courage to contact you for assistance, but I’m so glad I did. Although I knew for sure my ex-wife was living with her new boyfriend, I had no way to prove it. My attorney said if I had enough proof, alimony might be reduced and or eliminated. Thanks to you and your awesome team, we were able to gather a tremendous amount of evidence against her that proved everything I had been saying for years. My alimony is now terminated once and for all and I can move on with my life! I would highly recommend Dave’s services to anyone involved in a cohabitation case. He is patient, tenacious and very determined to get the evidence needed for his client!


  • Mr. David, I am sending you this email to simply say “Thank you” for getting the information and evidence I needed to prove that my employee, who claimed he hurt his back while working, was in fact not injured at all. Your surveillance skills and efforts are much appreciated.

    - ROBERT W. 4-12-22 HAMMONTON, NJ

  • Dear Dave & Team, you guys are amazing!! I don’t know how to put into words the amount of thanks and gratitude I have for you and the entire team for the way the case handled. As you know, most of the investigators I spoke with before contacting you, wanted to charge me a huge upfront retainer without even taking time to explain their process and how things would work if I hired them. You were the complete opposite! After our first phone conversation and initial meeting, we developed a game plan for surveillance based on my husband’s schedule and other important factors and the rest was in your hands. Great job Dave!

    - HELEN J. 3-23-22 CHERRY HILL, NJ

  • Mr. Ollivier, I just wanted to extend my sincerest “Thanks” for providing such a high-level of professional service to me and my boys during the most difficult time of our lives. You showed a great deal of compassion and concern for my family overall, and made me feel comfortable with the process of conducting surveillance on my husband. I will highly recommend your services to anyone who inquires. Thanks again for everything. Barb R.


  • Dear Mr. Ollivier, I am forever grateful for the way you and the team handled my case. You were very prompt in returning my frantic phone call and making time to meet with me in person so I could explain the situation in detail. The team did a great job doing surveillance on my wife, they went undetected for weeks and had no issues. Thanks again!


  • Dear Sir, the way you handled my case from the start truly set the tone for how the entire investigation was going to tourn out. You were concerned, compassionate, and very determined to get me the answers I needed. Your professionalism and caring attitude are truly commendable and well deserving of my thanks. Glad you were on my team!


  • Dave, my staff and I, along with my corporate attorney, would like to extend our sincerest thanks and appreciation for all your hard work over the last 3 months. Your and your team proved that my former employee was not injured as he claimed, but you also confirmed he was working a full-time job for our competitor doing the same type of work. I can’t thank you enough for your guidance and help.
    What an amazing team! Thank You! Thank You! Thank You!

    - JANICE Y. 11-2-21 BLOOMFIELD, NJ

  • I would strongly urge anyone who suspects their spouse or significant other is cheating to hire a professional investigator like Dave Ollivier. Dave and his team have the experience, the street skills and the best surveillance equipment available to obtain and record evidence. He even used a night vision video camera to catch my wife kissing her new love interest in the park at 11:30pm! Thanks Dave.

    - PETER W. 10-17-21 PRINCETON, NJ

  • Thanks to the efforts of Dave and his team, I was able to get my alimony terminated in court and receive back pay from my ex-wife for monies paid that were not owed because of her current living situation. Most men, like myself, don’t want to “rock the boat” and cause problems after a divorce, so we just deal with the burden of alimony each and every day. I will highly recommend your services to anyone in need of an experienced professional investigator.


  • Dave, my family, and I are so grateful for the time and effort you invested over the course of the last few weeks while looking into my great grandmother’s abuse case. It’s sad to think that your loved ones aren’t safe in a place that is supposed to be looking after them at this stage of their life. Your diligence and superior interviewing techniques resulted in the arrest and conviction of the nurse in charge of my grandmother’s care. Job well done!

    - STEPHANIE K. 9-12-21 BRICK TWP, NJ

  • I would highly recommend Blackstone’s asset recovery services for anyone who needs to locate and identify hidden bank accounts. After maxing out our credit cards before our divorce, my ex stole thousands from our joint bank accounts then opened a secret account to hide money. Within a few weeks, Dave identified the hidden accounts and provided me and my attorney with a substantial amount of information which was used in court. Thanks Dave!


  • Mr. Ollivier, I just wanted to drop you a note to let you know how grateful I am for your top-notch forensics team that was able to recover the extensive amount of accidentally deleted highly sensitive data from my laptop. Great job!

    - MARK T. 8-2-21 LUMBERTON, NJ

  • Dear Mr. Ollivier, many thanks to you for conducting a professional and thorough investigation involving the mistreatment and abuse of my grandmother by several nursing home staff members. Based on the video evidence and witness statements you obtained, I retained an attorney and am now suing the establishment that brough so much sorrow and despair into my life. Without your involvement, I would have been stuck fighting against the corporate attorneys alone with no proof.

    - STACEY R. 7-15-21 CHERRY HILL, NJ

  • Dave, thanks for finding out which employee was stealing money and product from my business. You blended in perfectly with my existing team members and by gaining their trust after only a few weeks, you found out all the information I needed, and I was able to terminate the employee without the fear of being sued.

    - GEORGE C. 7-4-21 FREEHOLD, NJ

  • To Dave O. and Team, I just wanted to say “Thank You” so much for taking the time to not only listen to my sad story, but to also make me feel calm and more at ease knowing I was in very good hands. When I found out my husband was cheating, I was devastated and had no idea what to do or who to call. Thanks for getting me the proof I needed before moving on with my life. You are a good man.

    - KAREN F. 6-17-21 CAPE MAY, NJ

  • For many months I suspected that my husband of 12 years was having an affair with an old girlfriend. All the signs were there, I just needed the proof. After interviewing many investigators, I decided to hire Dave O. based on his solid reputation and caring mannerisms during our first phone call. It wasn’t cheap, but after an in depth 4-week investigation, Dave provided me with an overwhelming amount of evidence that confirmed my suspicions. Everyone thought I was crazy, except for Dave. His tenacity and patience helped me get through the most difficult time of my life. I now have my family back and I’ve started a new chapter in my life thanks to Dave’s efforts!


  • Thanks to Dave and his team, I was able to obtain damning evidence against my ex-husband and his new girlfriend involving their improper treatment of my teenage son while in their care. My son endured verbal and physical abuse, and was forced to stay in his room while my ex and his girlfriend partied all night with friends in the backyard. Dave installed hidden cameras around the perimeter of the property in order to document the events. After an extensive court battle, I now have full custody of my son and I couldn’t be happier. My son is now in a much better frame of mind and doing well.

    - BARBARA D. 5-21-21 EVESHAM TWP, NJ

  • Dear Dave, I can’t begin to thank you enough for being one of the most honest and upfront professionals I have ever worked with. Trying to prove my ex-wife was living with her new boyfriend became a daily chore and almost ruined me. After we spoke, I knew I was in good hands and things would eventually come together. You told me to “trust the process” and things would work out, and I’m so glad I listened! Based on the evidence you obtained and provided, my alimony has been terminated and my ex-wife is required to pay me back a nice sum of money. You are the best in the business! Thanks for all your time and effort. I will highly recommend your services.

    - STEVEN L. 5-15-21 BRICK, NJ

  • Thanks so much for recovering the deleted texts and emails from my husband’s old phone. The information and evidence you recovered confirmed my suspicions about my husband’s affair. Thanks for your help and understanding. You are a true professional and a very kind person.

    - WENDY L. 4-10-21 PENNSAUKEN, NJ

  • Several months ago my wife and I noticed a significant change in our teenage sons behavior. He became more distant from us and his siblings, his grades dropped and seemed agitated all the time when we tried to talk to him. We tried counseling but nothing worked. A friend suggested we contact Dave from Blackstone Investigations for assistance since they had used him in the past. One month later, Dave and his team confirmed that our son was using drugs, spending time with the wrong crowd and sneaking out of the house. Thanks to Dave we are now back on track.


  • Dave, as you know, your kindness and genuine concern for my case was what led to me retaining your services. The level of technical skills and knowledge your forensics team displayed was great! I knew my boyfriend was cheating and using our home computer to chat with his new girlfriend, I just couldn’t prove it. Thanks for recovering all the deleted date he thought was gone forever.

    - MAGGIE S. 1-17-21 TOMS RIVER, NJ

  • I recently hired Blackstone to find assets and bank accounts that my soon to be ex-husband was hiding from me. Thanks to Dave and his team, I learned that he had been stashing money in several accounts that I knew nothing about. My attorney was able to use this newly found information and present it in court. In the end, I got what I deserved thanks to Dave and his diligent work. I would highly recommend his services to anyone.


  • Dear Dave, I wanted to say thanks for confirming that my teenage son was not being properly cared for while in the custody of my ex-wife during her shared custody parenting time.  As suspected, her drug and alcohol abuse were an ongoing issue, and her new boyfriend was verbally abusing my son. Thanks to the video evidence you obtained, my attorney was able to get me full custody due to the dangerous conditions my son was forced to deal with. Your time and patience is much appreciated!

    - HARRY T. 12-27-20 RIVERSIDE, NJ

  • My husband and I became victims of fraud to people we trusted and adored. We welcomed them into our lives and our very successful health care business. Little did we know, they had successfully hacked into our business computers and were stealing a vast amount of client’s personal information. After hiring local “forensic investigators”, we contacted Dave in New Jersey and explained the situation. He was exceedingly kind, considerate, and genuinely concerned for us. The decision was made to send our hard drives and other electronic equipment to Dave so they could conduct an in-depth forensic exam on all the devices. Several weeks later, Dave provided us with a vast amount of forensic information that our attorney needed. Thanks, Dave, for all your hard work.

    - STEVE & BONNIE J. 12-17-20 HARRISBURG, PA.

  • To Dave O. and the awesome team at Blackstone Investigations in Mount Laurel, New Jersey. I am so glad I chose you and your firm to conduct surveillance on my ex-wife so that I could finally prove she was living with her new boyfriend while continuing to take my monthly alimony payment. Your genuine concern, guidance through the process, and kindness truly had a major impact on me and the case. Thanks to you, my attorney and I were successful at getting my alimony terminated! The amount of evidence you obtained through difficult conditions over the course of a few months was spectacular and much appreciated. I will highly recommend you services!

    - BRIAN P. 12-5-20 MILLVILLE, NJ

  • Many thanks to you and your team for helping my family and I locate my missing brother. We really appreciate all that you did to make this dream become a reality!

    - Kim T. 12-2-20 Cape May, NJ

  • My firm hired Blackstone’s IT team to conduct a social media investigation on several employees who were allegedly posting negative comments and reviews about our company all over social media platforms. Within just a few days, Dave was able to retrieve both current and previously deleted posting from several fake social media accounts that were set up by the employees. Thanks to Dave we were able to discipline the employees without fear of repercussions. I would strongly recommend Dave and his team for any social media cases.

    - Barbara W. 9-12-20 Haddonfield, NJ

  • Dear Dave,

    I can’t even begin to tell you how special you truly are. The kindness, compassion and the amount of patience shown towards my husband and I during this troubling time was absolutely amazing! When you and your team took on my case involving the custody of my grandson, I had no idea how difficult the other parties involved would become. My grandson was in danger and living in a very unhealthy environment. Your tenacity during the investigation, and the way your team coordinated their efforts was top notch! Thanks to you, my grandson is now living with us full time and is finally safe! I will highly recommend your services to anyone who is dealing with a child custody case. Well done Dave!

    - Janet C. 9-1-20 Hammonton, NJ

  • As you know, I suspected that my fiance was having an affair during the time we were putting wedding plans together. I’m so glad I contacted you and hired your firm to conduct in depth surveillance on my fiance in order to uncover the truth about his infidelity. Everything appeared fine on the surface, but I now know he was just going through the motions. I sincerely appreciate your effort, your positive uplifting attitude towards me and the situation in general, and most importantly, your dedication to finding out the answers I needed and deserved. You save me a ton of aggravation…and I just wanted to say Thank You.

    - Mary H. 8-23-20 Short Hills, NJ

  • As a professional athlete, I typically have a hard time trusting and confiding in anyone, especially when it involves personal matter of this nature. After speaking with numerous private investigation firms, I spoke with Dave, and I can honestly say that from the moment we spoke on the phone I was comfortable with him, his background, his knowledge in the industry and his drive to satisfy his clients. He explained the pricing and the company retainer agreement, how the investigative/surveillance the process works, his video equipment, and the tactics he and his team utilize to document evidence. Needless to say, I was very impressed and hired him on the spot! The job is now completed, I am 100% satisfied and would highly recommend Dave and his team to anyone looking to hire a top notch private investigator! Thanks Dave.

    - Brian W. 4-20-20 Washington Twp, NJ

  • Dave and Team,

    I just wanted to drop you guys a quick “Thank You” for all your hard work and effort on my case. When I found out my ex wife had been living with her new boyfriend for over two years I almost lost it. My attorney suggested hiring a Private Investigator so I began my search, and after speaking with 5 different companies, I selected Blackstone Investigations, and I’m sure glad I did. You took my case personally and didn’t treat me as if I was “just another job”, and that goes along way with people when they are dealing with very strenuous circumstances. Our initial phone made feel more at ease after you took the time to explain the process of how things work. Once the judge reviewed the mountain of damning evidence you and your team provided, alimony was immediately stopped! Please say “Thanks” to the guys, it was a real pleasure working with them. Feel free to use me as a referral anytime!

    - Paul T. 2-23-20 Rockaway, NJ

  • Hi Dave. I just wanted to reach out and say “Thanks” for all your hard work and genuine concern for my case involving child support payments. After speaking with you on the phone, I knew you were the guy for the job! Thanks to you and your professional team, I was able to prove in court that my two sons WERE NOT full time students therefore allowing me stop paying huge amounts of child support that wasn’t required by law. You saved me a ton of money and I am eternally grateful to you!

    - Peter Y. 9-3-19 Medford, NJ

  • I own a property management company in South Jersey, and have recently contracted with Blackstone Investigations Group, LLC to conduct in depth background checks on all of our new tenants wishing to move into one of our communities. Dave’s ability to access database information on applicants that nobody else has access to has proven to be an invaluable tool for us and has saved my firm thousand in legal fees since we now know peoples background information BEFORE they move in. I would highly recommend using Dave and his team for your background check needs.

    - CPM Management, LLC. 6-5-19

  • “I am proud to say that I have recently begun using the professional services of Blackstone Investigations Group for several family matter type cases and have been thrilled with the results.  After being in business for many years, I fully understand the importance and value in using professional investigators, but unfortunately, many of the investigators that I have utilized in the past have not satisfied or met the level of professional that I expected. Dave is sincere, tenacious and is truly dedicated to customer satisfaction and taking care of my clients. Whenever the need arises for a Private Investigator, the only name that I consider for my clients now is Dave Ollivier and the team at Blackstone Investigations Group.  I have no reservations endorsing Dave and his firm for any type of investigative assignment!”

    - Diane Bowman, Esq. Bowman Law Offices 2-15-19 Trenton, NJ

  • “Mr. Ollivier, I cannot thank you and your team enough. Your professionalism is without question. I have used many investigative firms in the past in business when I need information regarding who I am doing business with. I have never used such a firm for personal matters and I must admit that your conduct goes so over and above what others can or are able to do. I walk from this knowing the following: That you are incredible and that I have actually made a new friend who cares about and understands feelings… This above anything else makes this difficult situation easier and makes me smile… Your advice has been invaluable and only through the pleasure of meeting you to say the words of thank you can I truly express my gratitude.”

    - John S. 1-18-19 Medford, NJ

  • “I wanted to write to express my complete satisfaction with the service provided by Dave and the team at Blackstone Investigations Group. We needed to find out the truth about our opponents activities, and Blackstone gave us the answers.  I was extremely impressed with their professionalism and the short turnaround time in which they were able to obtain the information we requested.  If the need ever arises I would not hesitate to call on them again for their services.  I also will not hesitate to recommend your firm to any of our clients who may be in need of your services.  Once again, thank you very much for an excellent job and your professionalism.”

    - Joan D. Esq. 12-17-18 Mullica Hill, NJ

  • “Dave, you are the best! Thanks so much for working with me in the most troubling of times. For a long time, my husband and I worried about the friends our daughter was really spending her time with and whether or not she was using drugs. The information you provided was critical in helping us find out the truth and begin mending the broken relationship and trust issues we have with her. You have helped bring our family back together!”

    - Jessica R. 9-23-18 Marlton, NJ

  • “It is rare that you find a professional of such stature that maintains his integrity, honesty, and privacy, I would recommend Mr. Ollivier and his firm to anyone in my family and amongst my friends as well as anyone else who is in need of any assistance from an all-purpose firm. Mr. Ollivier, will not simply investigate matters for you, he will take care of your interests in a manner that is very rare in today’s society.”

    - Bridgette O. 9-4-18 Cape may, NJ

  • “It is with great pleasure that I write this recommendation for your services. When my son had run away from home last summer, I feared I would not see him again. Thanks to you and your work, we were able to reunite within days and work out whatever issues had surfaced.”

    - William E. 5-3-18 Red Bank, NJ

  • “Dear Dave, I’m so glad I found your company and used your services to run my boyfriend’s background and criminal history check. My family members and friends were suspicious of him, but I didn’t see it. Thankfully, your investigators found out information about him that I didn’t even know existed and helped me through a tough time. Needless to say, I broke up with him and am now much happier and safer.”

    - Emily J. 4-12-18 Vineland, NJ

  • “Dear Dave, I wanted to let you and your staff know how truly grateful I am for the wonderful, professional and caring services your company provided during one of the most difficult times in my life.  Going through a divorce in itself is very tough, but then to find out your ex-wife has been living with her new partner while I’m paying her alimony every month made things even worse! With the evidence you provided, my attorney was successful in getting my alimony eliminated! You’re the BEST! Thanks again for caring about my situation and helping me get the proof I needed.”

    - Jonathan R. Esq. 2-21-18 Cherry Hill, NJ

  • ”Hiring Dave and his team was the best thing we could ever do to find out what our teenage son was actually doing. Dave found out all the information we needed to know in a very short period of time. Thanks for doing such a great job Dave!”


    - Susan D. 11-2-17 Hamilton Twp, NJ

  • ”After speaking with several other investigators, I felt the most comfortable working with Dave and his team of investigators. The situation was already stressful enough but Dave made me feel comfortable and gave me the peace of mind I needed to know that someone was actually looking out for me. He worked within my budget and got me more evidence and proof that my suspicions were right; more than I could possibly imagine. Thanks Dave for making a difficult situation a little bit better! I will highly recommend your services.”

    - Stan J. 04-12-17 Ocean City, NJ

  • “Dear Dave, just felt the need to say “Thanks” for catching the employee who lied about being injured on the job and work and then trying to collect workers comp pay while working another job. It’s unbelievable what some people will do to work the system to their advantage.

    - Stephen Y. 2-6-17 Toms River, NJ

  • Marine Corps Veteran