Research and analysis

MILLWEC barb change recommendations letter

Updated 11 May 2026

Professor Charles Deakin
Chair of the Medical Implication of Less Lethal Weapons Expert Committee
2 Marsham Street
London
SW1P 4DF

6 February 2026

Dear Use of Force Policy Lead,

Commission to the Medical Implications of Less Lethal Weapons Expert Committee to consider the significance of the Taser 10 barb change

1. Thank you for the commission received on 20 January 2026 requesting that the Medical Implications of Less Lethal Weapons Expert Committee (MILLWEC) provide advice on whether the new Taser 10 barb (the laser cut spear design) represents a significant change to the Taser 10 device, when compared to the older ‘fishhook’ design. The Taser 10 device with the older barb was assessed by the Science Advisory Committee on Medical Implications of Less Lethal weapons (SACMILL), MILLWEC’s predecessor.

2. The MILLWEC Chair and 5 Members met on 2 February 2026 to discuss and formulate their advice to the Home Office on the matter outlined above. This meeting was also attended by the Head of Science Advice Delivery as an observer.

3. Prior to this meeting, the evidence documents provided by the Home Office were circulated to all attendees for their consideration.

Considerations

i. Significance of change

4. MILLWEC defined ‘significant change’ in relation to Taser 10 as any change that requires alteration to the current standard operating procedure for the conducted energy device (CED). This included: increased risk of harm, a change to the medical care that someone would require after a CED has been used on them, a change that would require alterations to how the CED was operationally deployed or a change that requires those deploying the CED to undergo different training.

ii. Depth of skin penetration

5. MILLWEC noted that the independent comparative test report found that the new barb penetrated the skin an average of 4.1mm deeper than the older barb design.

6. MILLWEC Members discussed whether the increased depth of skin penetration was likely to be significant. Whilst recognising the uncertainty given the lack of specific data, they considered that the geometry of the new barb likely contributed to an increased depth of tethering in the skin, rather than necessarily an increased depth of initial penetration. The facts that the technical testing found no significant difference in the probe velocity or kinetic energy, and observed an increased rate of pinprick marks left on the bone by the older barb design, further contributed to the Committee’s conclusion that the increased depth of skin penetration was unlikely to be significant.

7. One consideration was whether there was an increased likelihood of hitting a vulnerable organ beneath the skin, due to the increased skin penetration. Bodily areas of particular concern include areas where the skin is thinner including: the heart, pleural cavity, around the collarbone, the brachial artery and windpipe. In their original assessment of the older barb design, SACMILL concluded that there should be an increased emphasis on targeting the thighs when using the Taser 10 to avoid the potentially more serious injuries to more sensitive areas. MILLWEC would further emphasise this recommendation.

8. MILLWEC concluded that the initial penetration of the probe was likely to be similar in both barb designs. There is currently no evidence that this represents a clinically meaningful difference.

iii. Other considerations

9. MILLWEC also considered the barb geometry, probe removal, risk of requiring medical intervention and risks to vulnerable groups. They concluded that there was unlikely to be any significant difference in medical implications between the older barb design and the new barb design

Recommendation

10. Following this discussion, MILLWEC unanimously agreed that the new Taser 10 barb design does not represent a significant change when compared to the old design approved by the Home Office in October 2025.

11. However, MILLWEC would like to highlight the challenges in making this assessment posed by the lack of operational data available. As such, MILLWEC would further endorse the recommendations made by SACMILL to monitor operational performance (Recommendation 11), and to inform MILLWEC of any significant deviations from the medical implication assessed in the original statement to enable further assessment (Recommendation 13).

12. In future, MILLWEC would additionally find further operational data on the use of CEDs on vulnerable body areas and co-morbidities arising from this relevant when assessing medical implications. MILLWEC would recommend that the Home Office should seek to provide this data where possible.

13. Thank you again for your commissioning letter and for providing the available evidence for MILLWEC to consider. I look forward to your response to MILLWEC’s recommendations in due course.

Yours sincerely,

Professor Charles Deakin

Chair of MILLWEC