David Smith 00:00

Welcome to The Expert Witness Podcast. I am your host, David Smith, and I’m excited to be here today with Eric Rose. Eric has over 40 years’ experience developing new products in the consumer medical and industrial product markets. He’s worked with companies such as Mattel Toys, American Hospital Supply, Brown Jordan Furniture and Sunrise Medical. Products he’s worked on include Disney infant preschool toys, disposable medical devices, dental devices, durable medical equipment, patio furniture, consumer electronics, and personal protective equipment such as earplugs and N95 masks. Eric’s education includes a Bachelor’s of Science in Industrial Design, also known as product design, and an MBA. Eric was certified as a new product development professional (NPDP) in 2008. He is a member of the American Society for Quality and sits on the board of directors of the Society of Plastics Engineers Product Design and Development Division. Eric has taught product innovation and related subjects at the university level since 2009 at schools such as Pepperdine University, Loyola Marymount, and Rice University.

David Smith 01:22

He has been a public speaker since 1985 on a wide range of topics from plastic product design and manufacturing to product liability. Eric began his expert witness journey in the spring of 2020 when he was tapped to be a product design expert witness in the 3M military Earplug case where he was deposed by 3M for seven hours. He currently serves as an expert witness working with both plaintiff and defense counsels on commercial dispute, patent infringement, and product liability cases. Eric, welcome to the podcast. It’s a pleasure to have you here.

Eric Rose 02:01

It’s a pleasure to be with you today, David.

David Smith 02:04

All right. So one of the first questions I always like to ask is, how did you get into expert witness work? Seems to be a little known career choice. It’s not something that people usually talk about when their kids. So, I’m always curious how were you introduced to it and, and how that process happened?

Eric Rose 02:23

Sure. I’ll start with a slight digression. When I did my undergraduate degree at Arizona State in product design, I had a course in product law and I was fascinated by the course. It was half product liability and half intellectual property law, patent law primarily. And so I always had a heightened awareness of how product and law could intersect. Fast forward to the spring of 2020, and I was reached out by a law firm, reached out to, by a law firm in New York who said they had this 3M military earplug case and thought that I might be a good expert witness. Well, it turns out that from 2007 through 2011, I was the research and development director for Moldex-Metric, also known as Moldex, and they make earplugs and N95 masks. And because I had that expertise, I figured, well, that makes sense for me to be able to participate again in this intersection of law and product. And I was pleased to be on that project, that 3M ear plug project for about a year.

David Smith 03:36

All right. That’s, great. That’s really interesting. And we actually wanted to talk more about that 3M Earplug case today. Now, I understand that in that case, 3M’s Earplugs were found defective resulting in a $6 billion settlement. If I understand, that’s the largest multi-district litigation to date. With over 250,000 plaintiffs. That’s really interesting. So can you tell us real briefly, what is a multi-district litigation?

Eric Rose 04:16

Sure. I’m not an expert in that topic, but unlike a class action where individuals are consolidated into a single lawsuit, multi-district litigation, also known as MDL, involves the court grouping together similar cases and adjudicating them in a single court. So in this case, it was the Southern District of Florida where this one judge was the court to manage these quarter million cases. And I was involved with that.

David Smith 04:55

Okay. And so as an expert, did you work on multiple suits within this multi-district litigation, or how does that work?

Eric Rose 05:09

Yes, so the New York Law firm retained me and they had a few clients, I don’t remember exactly how many plaintiffs they were representing, but it was a, what was called a bellwether. So the intent was to have a few bellwether cases that would address various issues in the case to see how they did, and used that to test for the rest of the cases. And so this was a very early case that I worked on, and primarily for one small set of plaintiffs that was followed by a second grouping of attorneys out of Kansas, and that was another case that had, I think they had two plaintiffs that they represented.

David Smith 06:05

Okay. And so do you know, were there a bunch of other plaintiff’s experts that were doing kind of the same thing as you

Eric Rose 06:15

I don’t know. I’ve never heard of any other product design, expert witness addressing what I did. That is the product design, development, manufacturing, quality, from a product design perspective, I don’t know of any other such experts, but they may be out there.

David Smith 06:36

Okay. Oh, that’s interesting. So I’m curious, how were you initially contacted about this case? You said it ended up being almost a year’s worth of work. Was it just a cold call one day where you happened to be in the office or how did those attorneys find you?

Eric Rose 06:54

I can’t recall. It’s been so long and back then I wasn’t really tracking any of this. My recollection, it might have been through LinkedIn. I have a presence on LinkedIn. I certainly have a presence through my website. I have a presence through my academic work. And again, with my experience at Moldex being the research and development director of personal protective equipment, I suspect there’s probably only a handful of people in this country that could opine on the product design development of an earplug that also have enough public speaking experience including my academic work teaching at the university level to be that mix of as you know, what it takes to be a good expert.

David Smith 07:46

Yeah, absolutely. There’s certainly additional skills in excess of just understanding the engineering principles that are required to be a good expert.

Eric Rose 08:03

I like to say making the technical understandable

David Smith 08:07

That is a topic that keeps coming up in these. And it’s so true. Just being able to, you know, dumb it down or de jargon it or just make it understandable for anybody. It’s so important in these cases.

Eric Rose 08:28


David Smith 08:28

It’s always interesting to me with this type of work though, how the amount of work you have ahead of you can change in a day or two. There have been times in our business where we’ve had, you know, a, a fairly light forecast and, and then within a week we get three or four new cases and all of a sudden everybody is, you know, slammed with work you know, and some of these cases, like you said, last a year or two or three or four even. And so it’s interesting that way. It makes planning difficult sometimes, but it’s a fun place to be.

Eric Rose 09:21

Keeps you on your toes

David Smith 09:23

For sure. All right. So going back to this 3M Earplug case it sounds like you opined that the earplugs were defective because they didn’t penetrate far enough into the ear to form an effective seal. Is that correct?

Eric Rose 09:44

Yes, essentially that is correct. And this is public information out on the internet. A number of law firms have published pages like a white page almost on what happened and so forth. So it’s not anything confidential. So there’s this idea, some people talk about this, the butterfly effect, where one little thing can have huge downstream effects. And essentially it was my opinion that’s what happened in this case, that the 3M company had a design that they were developing on spec for the government. There was no contract between the government and 3M to say that the government wanted a particular design, but 3M was developing it, and the government was providing some commentary. One of the bits of commentary the government provided was that they wanted this earplug, this dual ended earplug, which is pretty long for an earplug to fit in one of their earplug cases they already had. In order to do that last minute, 3M made a change, and that change was to shorten the distance between the two ends of the earplug, and the two ends of the earplug were originally about 3/32 or so greater.

Eric Rose 11:16

But by shortening that one side of the earplug, now that side of the earplug could interfere with surface of the ear and the surface of the ear then would push the earplug back out and in what was called imperceptible loosening. And if you know anything about acoustics, if you break an acoustic seal, then that sound, noise, gunshot, mortar fire, whatever it might be, that reverberation can end up in your ear causing injury. And essentially that is what happened.

David Smith 11:55

That’s really interesting. So talk to me a little bit about the work that you did to be able to generate and support your opinions.

Eric Rose 12:07

Sure. There was a big team on this case. There were numerous experts, audiologists, academics who were experts in this space, people who built an artificial ear for testing simulating jaw movement, all these kinds of experts that were on the case. Very interesting. I had to review their work, I think printed out, it was about almost four feet worth of binders on my desk. My desk wasn’t even big enough, thousands of bits of information. And ultimately, I had to consolidate all of that plus my 35 plus years’ experience in plastic and rubber part design, going back to my undergraduate courses in human factors, plastic part design, tooling. All of that came into play where I was able to then opine on the weaknesses of the design, the development, including ISO 9000 issues and testing and supporting documentation that any responsible manufacturer would do.

David Smith 13:31

Yeah, it’s interesting you talk about four feet of binders worth of information that, you know, goes into how a product is designed or could be designed, or things that they could have or should have looked at. And I think in product development in general, people think it’s a, a quick and easy process, and they don’t realize how much research, how much development, how many different things have to be looked at in order to put a product like that on the market.

Eric Rose 14:01

Well, we often talk about foreseeable misuse. So, if you’re looking at what is called a, failure mode and effect analysis, right? It’s understanding what is the real-world environment that this product is going to be used in. If you’re a military person in Iraq, in the middle of the summer, running, jumping, crawling, these are all important attributes for an earplug, for example. But any piece of item, any product you develop needs to have that kind of analysis done to ensure the product in the end is safe and effective.

David Smith 14:39

Yeah, I couldn’t agree more. That’s, one of the things that we help companies with. Now, I don’t know if you’ve noticed this, but we’ve found that a lot of companies, a lot of engineers, they’ll put their heart and soul into designing this cool product, and it’s so difficult for them to turn around and say, okay, now what’s wrong with it? How is it going to fail? You know, what are people going to do with this that I’m not expecting? And so it can often be very helpful to involve a third party in that risk assessment or failure modes and effects analysis.

Eric Rose 15:18

Absolutely. I read the quality manual, the quality book from Juran, and that’s exactly what he talks about. A failure mode effect analysis is really, and same thing with design reviews. They are most effective when a third party, those that not involved with the design are involved in the critique to ensure a beginner’s mind in some regards, or experts in other areas such as manufacturing or the user, they’re human factors they’re looked at with that outside eye.

David Smith 15:50

Yeah, absolutely. So after you had generated these opinions for the case, how did you present your findings? What did you do to make it easy to understand and easy to digest for anybody that was listening?

Eric Rose 16:09

Sure. So there’s really two parts of that answer. First for the report, the expert report, I had numerous illustrations, cross sections of the earplug, notes, details, dimensions, dimensions before the change, after the change. Implications of that marked up drawings highlighted excerpts from independent sources such as human factors textbooks, US military training book was included as reference non-military US government standards. You and I had talked about the EPA being one of the regulatory bodies involved with rating earplugs noise reduction rating, plastic part design standards. Again, going back to my undergraduate degree, ISO 9001 was a big one. Design control, design review standards and much more trying to keep things simple when it came to the report. 


On the deposition side, it’s really about drawing analogies, simple analogies, whether it’s about building and testing a car, making sure that you’re testing the car with the right tires and wheels that are on the product in the final car, not testing individual bits and pieces, and then trying to draw conclusions that when assembled, it works. Same thing with the analogy I use sometimes about building a house. When you design a house, you want design specs, three bedroom, two bath, two floors, swimming pool in the back. Well, it’s important that when the house is all done and you inspect it, it’s not one bedroom, one bath with a swimming pool in the front yard. So being able to use simple analogies as to what did or did not happen, I found was very productive as well.

David Smith 18:05

Yeah, absolutely. Those relatable metaphors not only help them understand it, but also helps it stick in their mind as well. So it’s not just, you know, some drawing that they saw, but now they can really understand and remember why that drawing was important.

Eric Rose 18:24

Something relatable, yes, absolutely.

David Smith 18:30

Right. So I understand you were also the subject of a Daubert challenge in this case. Is that correct?

Eric Rose 18:40

Yes. So the court has the responsibility to ensure that the expert is an expert, and you and I, I think in the past have talked about some of the new rules about the Daubert and making sure that this methodology is sound. So I was able to use 3M’s documents ISO 9001 documents, independent textbooks and other credible peer reviewed, supporting documents and used that as my methodology so that it wasn’t Eric Rose’s opinion. It was Eric Rose as a voice to these credible, independent sources of fact that had become acceptable in the industry such as ISO 9001 or 3M’s quality management system, whatever they were. And because I did that in the end the court stated, I’ll just quote a couple things here. “The defendants do not challenge Rose’s qualifications or his opinions that Aearo, a division of 3M, violated industry and internal corporate standards. Rather, they seek to exclude his unsupported leap to the conclusion their alleged violations increase the risk of product defect.” So in the end, the last thing the court said was, “Rose’s, analytical steps are clearly articulated and substantiated by a verifiable factual basis, which meets the precision and specificity requirements of Rule 7 0 2 and Daubert.”

David Smith 20:34

Yeah, that’s sounds like the best outcome you could get from a Daubert challenge.

Eric Rose 20:42

I would say that was pretty darn good, but it was, again, it was based on careful application of this methodology That was not Eric Rose’s opinion, it was Eric Rose as a voice to these fundamental facts.

David Smith 21:00

Yeah, absolutely. That’s one of the things that we teach now all of our experts, is if your opinion is, if the basis of your opinion is that’s just the way it is, because I know or because I say, so that’s not going to work. You’ve got to go back to some testing, you’ve got to go back to a textbook, you’ve got to go back to a standard, and then all you’re doing is explaining and presenting what’s already been documented and is well known.

Eric Rose 21:35

It’s supporting the trier of fact.

David Smith 21:38

Yeah, absolutely. Just giving, presenting the information that they need to make the right decision. So talking a little bit more about the Daubert challenges and trying to get experts excluded, it seems that at least in high value cases, that’s a very common strategy for one or both sides to take, is to try and get the other expert excluded. And, you know, oftentimes you’re asked as an expert, have you ever been the subject of a Daubert challenge, which I would imagine a lot of experts have. You know, if you haven’t, you probably haven’t done a lot of this work. But that’s very different than being excluded as a result of a Daubert challenge. And so I think that’s an important clarification to make for a lot of people that just being challenged is not a bad thing. You know, in this case where you were challenged, it sounds like it was actually a good thing and the court said, Hey, he is an expert and we like the way he presented his information. And it seems very clear and it seems like it’s done right. It’s almost like there challenge backfired and instead of making you seem less credible, the court buoyed you up and said, wow, he really is credible. You should listen to what he says.

Eric Rose 23:15

Yes. I think that’s a fair statement. I was actually surprised that 3M did not challenge my qualifications. Maybe there was something they could find that they felt I didn’t have 20 years’ experience of earplug design or something to that effect. But no, they didn’t, and that was great. Nor did they challenge my opinions that they had violated industry and their own internal corporate standards, because that was hard for them to refute that. I was surprised, but pleased that I wasn’t really challenged there.

David Smith 24:08

Yeah, absolutely. So I think you had mentioned that this was your first case as an expert witness, is that right?

Eric Rose 24:17


David Smith 24:18

What was that? I mean, now that you’ve done this a little bit more, what was it like working on such a big and what has become a very high profile case as, as your very first experience

Eric Rose 24:31

Getting thrown into the deep end of the pool with inadequate swim training and maybe a couple floaties on my arms, that’s about it. Fortunately, I’ve been in my own consulting business now, it’s about a dozen years and after 35 plus years’ experience working at the corporate level, including being in the boardroom at Mattel toys and having to pitch new products and strategies. I’ve had some trial by fire, and certainly this was an incredible inaugural voyage into my expert witness world. But I feel like I came out the other end okay. I was retained by the second firm in the same MDL. And since then have worked on another maybe 10 or so cases and enjoy the work. It’s a wide variety now for me of product liability. I’m currently working on a commercial dispute case in the PPE industry, N95 mask case, and also did a patent infringement litigation case. So I love those three types of cases, and I believe the 3M Earplug case really set the stage for me to be able to do this work and it’s growing quite quickly for me, and I’m enjoying it.

David Smith 26:03

Yeah, that’s great. So, I’m curious if there’s anything that you learned from the attorneys or from the process being involved in such a large and public case things that you might think every expert should know.

Eric Rose 26:24

So there’s a couple things. I think first of all, these cases take longer than you ever imagined.

David Smith 26:31

That’s the truth.

Eric Rose 26:33

Yes. I’m not sure what alternative universe these cases run in, but in new product development, it’s always about decreasing time to market to get a new product out. But in the legal world, there’s court schedules, attorney schedules, and the other thing that I learned besides that things take longer, is that schedules are out of your control for the most part. Primarily they’re driven by the court. Secondarily, there’s attorney issues, they’re juggling cases, and then downstream there’s the expert. So one day the attorney will call up and say, sorry, we have to change our review session from x date to y date, and there really isn’t much of an option. So you’re juggling to move other appointments around accordingly. And I’m learning to get used to that.

David Smith 27:34

Yeah, it is a little bit different than normal product development work. You know, you could have a case that sits dormant for 3, 4, 5 months, maybe even a year, and then all of a sudden you get a phone call and they need something in a week. That’s not terribly uncommon, unfortunately. But that’s the way this industry works, I guess.

Eric Rose 28:04


David Smith 28:06

So aside from earplugs what other types of cases do you typically work on? I know you talked about patent cases and commercial disputes but what, what sorts of products or devices do you like to work with?

Eric Rose 28:32

So, for most of my career, I’ve worked in consumer products, I mentioned Mattel toys. I worked in the furniture industry. I like medical products. I started my career in the disposable medical device industry with American Hospital Supply. I moved into durable medical equipment, was working for the world’s largest manufacturer of wheelchairs, at the time was Everest and Jennings. I joined Sunrise Medical, one of the premier durable medical equipment manufacturing distributors in this country. So I’ve done canes, crutches, walkers, wheelchairs, hospital beds, home care beds, all of that type of work. Dental devices, extensive amount of dental devices, both durable and disposable. And then industrial products. Primarily the industrial products I’ve worked on include PPE, earplugs, earmuffs, industrial full-face respirators, used in factories, half masks, and N95 masks, all of that. So I love those three categories. I often say I don’t do the Fs, I don’t do food, fashion, pharma, or flying objects. So no aerospace.

David Smith 29:55

Very good. Very good. All right. So if you could go back, is adding expert witness work as a service, you provide something you would do again,

Eric Rose 30:08

Definitely. In fact, if I knew about it earlier in my career, I probably would have looked at what credentials, what study, I could do in order to expedite my involvement with it. Again, coming back to this discussion of the intersection of law and product, I just find that fascinating. I always have worked well with chief legal counsel in the firms I’ve worked for. In fact, the last two companies I worked for before going out on my own, chief legal counsel and chief operating officer were my bosses. And so getting that experience was just great. And if I could have done it sooner, I probably would have. But I’m enjoying it quite a bit now.

David Smith 31:06

Yeah, that’s great. You’ve certainly got a wide variety of experience that you can apply to different cases. So that’s swings in your favor for sure.

Eric Rose 31:19

Yes, thank you.

David Smith 31:21

That’s also, you know, like you said, a lot of people just don’t know that this is a service that they can offer. And there’s, I’ve found there are a lot of people that have been doing expert witness work for a number of years that are getting to the point where they’re retiring. And it seems like there’s the same problem in a lot of industries, but there’s sort of a big gap or a vacuum that’s starting to generate right now that’s going to need to be filled. So one of the things that we’re hoping to do with this podcast is to introduce people to this type of work and give them some tips and tricks to get into this type of work and to be able to do it well and properly.

Eric Rose 32:13

That’s great. In fact, I’ll share this ultimately when it’s done with my LinkedIn followers. I have about 8,000 followers now on LinkedIn, and I think it’d be a great way to promote the work that you’re doing, and I appreciate what you’re doing.

David Smith 32:25

Yeah, absolutely. So the last question, a lot of attorneys, you know, we send this out to our list of attorneys and hopefully others listen to it as well. But how can they find you if they’re looking for an expert on the types of things you might be able to help them with?

Eric Rose 32:44

Sure. Lots of different ways to find me. If you search on LinkedIn for Eric Paul Rose, you will find me. My website is, You can check out my website. My services section includes multiple pages on expert witness work. And if you just are looking for me online, you can always just Google “Eric Paul Rose, product design expert witness,” and you’ll find me through a number of expert witness registries as well as my own website.

David Smith 33:27

Awesome. Well that’s great. Well, Eric, thank you for being here today. Thank you for sharing with us your experiences on this 3M earplug case and your other insights. It’s been a pleasure.

Eric Rose 33:40

It’s been my pleasure. Thank you for having me, David. Much appreciated.



Connect with Eric at  and visit his company Pinnacle Product Innovation, Inc., at


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