In the US are new product safety features implemented by manufacturers ipso facto proof that they were aware their earlier products were unsafe?

Question

I've been reading up on features to make table saws safer and in one forum there was a post that said, basically, manufacturers have had no incentive to license a table-saw safety device from the inventor because doing so would only increase their exposure to product liability lawsuits relating to their older models: developing a safety feature themselves or licensing one developed by a third party would be ipso facto proof that they are aware their previous models are unsafe. In the US product liability arena is there really such a paralyzing disincentive for manufacturers to make safety improvements to their products? Does a manufacturer really incur risk by making safety improvements?

Answer 1

In order to avoid this perverse incentive, Rule 407 prohibits the use of subsequent safety measures as evidence for liability:

Rule 407. Subsequent Remedial Measures

When measures are taken that would have made an earlier injury or harm less likely to occur, evidence of the subsequent measures is not admissible to prove:

• negligence;
• culpable conduct;
• a defect in a product or its design; or
• a need for a warning or instruction.

But the court may admit this evidence for another purpose, such as impeachment or — if disputed — proving ownership, control, or the feasibility of precautionary measures.

https://www.law.cornell.edu/rules/fre/rule_407

Answer 2

No.

Quite likely, the manufacturer is increasing their risk if they don’t incorporate known safety improvements

australia

Product liability law is nicely summarized here.

With respect to older products it says:

Expected levels of safety differ for older products because they cannot be expected to be as safe as brand-new products. Similarly, older models of products would not necessarily be considered defective simply because more recent models have improved safety features.

And, one of the things a court must consider is “the time when the product was supplied” which includes considering what was reasonable practice at that time.