---
type: "Bill"
title: "Generally revise child safety restraint system laws"
description: "Generally revise child safety restraint system laws"
jurisdiction: "us/states/mt"
legislature: "Montana Legislature"
session: "2025"
identifier: "HB 586"
citation: "Montana HB 586 (2025)"
classification: ["bill"]
subjects: ["Minors", "Traffic Regulations", "Transportation"]
status: "enacted"
primary_sponsors: ["Marc Lee"]
version_count: 56
action_count: 41
vote_count: 10
first_action: "2025-01-18T16:16:15+00:00"
last_action: "2025-05-19T22:27:02+00:00"
source: "openstates"
source_identifier: "ocd-bill/6a05e890-669d-4bc1-8c8f-966cabf2495f"
source_url: "https://bills.legmt.gov/#/laws/bill/2/LC4324?open_tab=sum"
source_hash: "9e691d2b1bd0b612f58d3c5343d523acfb54c40932aa3553c91b849f21265b1a"
vintage: "2026-07-01"
source_snapshot: "https://data.openstates.org/daily/2026-07-01/public.pgdump"
retrieved_at: "2026-07-06"
confidence: "reported"
tags: ["legislation", "bill", "us-mt"]
---

# Montana HB 586 (2025) — Generally revise child safety restraint system laws

## Version chain

The bill's text revisions, in order — the diff chain from filing to enrollment.

1. **HB0586.001.001_Amendments-in-Context_final-full.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=289614)
2. **HB0586.002.001_Amendments-in-Context_final-full.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=294971)
3. **HB0586.002.001_Amendments-in-Context_final-not condensed.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=294973)
4. **HB0586_1(1).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=284443)
5. **HB0586_1(2).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=285035)
6. **HB0586_1(3).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291069)
7. **HB0586_1(4).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291070)
8. **HB0586_1(5).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291071)
9. **HB0586_1(6).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291072)
10. **HB0586_1.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=284442)
11. **HB0586_2(1).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291074)
12. **HB0586_2(10).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298286)
13. **HB0586_2(11).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298287)
14. **HB0586_2(12).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298288)
15. **HB0586_2(13).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298289)
16. **HB0586_2(2).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291075)
17. **HB0586_2(3).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291076)
18. **HB0586_2(4).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291077)
19. **HB0586_2(5).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291078)
20. **HB0586_2(6).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291079)
21. **HB0586_2(7).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=293842)
22. **HB0586_2(8).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=293999)
23. **HB0586_2(9).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=295636)
24. **HB0586_2.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=291073)
25. **HB0586_3(1).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298291)
26. **HB0586_3(10).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=304165)
27. **HB0586_3(11).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314112)
28. **HB0586_3(12).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314113)
29. **HB0586_3(13).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314114)
30. **HB0586_3(14).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314115)
31. **HB0586_3(15).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314445)
32. **HB0586_3(16).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314451)
33. **HB0586_3(17).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314453)
34. **HB0586_3(18).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314455)
35. **HB0586_3(2).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298292)
36. **HB0586_3(3).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298293)
37. **HB0586_3(4).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298362)
38. **HB0586_3(5).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298363)
39. **HB0586_3(6).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298364)
40. **HB0586_3(7).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298366)
41. **HB0586_3(8).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298367)
42. **HB0586_3(9).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298369)
43. **HB0586_3.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=298290)
44. **HB0586_X(1).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314457)
45. **HB0586_X(10).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=325079)
46. **HB0586_X(11).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=327133)
47. **HB0586_X(2).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314459)
48. **HB0586_X(3).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314768)
49. **HB0586_X(4).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314769)
50. **HB0586_X(5).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=317198)
51. **HB0586_X(6).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=320747)
52. **HB0586_X(7).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=323302)
53. **HB0586_X(8).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=323303)
54. **HB0586_X(9).pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=323304)
55. **HB0586_X.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=314456)
56. **LC4324.pdf** (committee substitute) — [source](https://api.legmt.gov/docs/v1/documents/getContent?documentId=281902)

## Votes

- Do Concur — **63–37** (pass) · lower
- Do Pass — **80–19** (pass) · lower
- Rerefer to Transportation-Tempel — **32–18** (pass) · upper
- Do Concur — **28–22** (pass) · upper
- be_concurred_in_as_amended — **7–1** (pass) · upper
- Do Concur — **30–20** (pass) · upper
- Do Concur — **73–26** (pass) · lower
- Do Pass — **84–14** (pass) · lower
- be_concurred_in — **8–0** (pass) · upper
- do_pass_as_amended — **12–2** (pass) · lower

## Sponsors

- Marc Lee — primary (person)

## Timeline

The legislative action history — every referral, reading, and vote.

- **2025-01-18T16:16:15+00:00** (LC) Drafter Assigned
- **2025-02-11T20:05:32+00:00** (LC) Draft in Legal Review
- **2025-02-11T22:36:48+00:00** (LC) Draft in Edit
- **2025-02-13T16:23:28+00:00** (LC) Draft in Input/Proofing
- **2025-02-13T18:51:35+00:00** (LC) Draft in Final Drafter Review
- **2025-02-13T19:49:04+00:00** (LC) Draft in Assembly
- **2025-02-17T14:02:59+00:00** (LC) Draft Ready for Delivery
- **2025-02-18T16:44:17+00:00** (LC) Draft Delivered to Requester
- **2025-02-19T21:48:17+00:00** (H) Introduced
- **2025-02-20T18:56:10+00:00** (H) Referred to Committee - (H) Transportation `referral-committee`
- **2025-02-20T19:51:28+00:00** (H) First Reading `reading-1`
- **2025-02-21T21:12:06+00:00** (H) Hearing - (H) Transportation
- **2025-03-01T01:01:41+00:00** (H) Committee Executive Action--Bill Passed as Amended - (H) Transportation `committee-passage`
- **2025-03-01T22:45:00+00:00** (H) Committee Report--Bill Passed as Amended - (H) Transportation `committee-passage`
- **2025-03-05T23:45:00+00:00** (H) 2nd Reading Passed `reading-2, reading-2`
- **2025-03-07T16:54:00+00:00** (H) 3rd Reading Passed `passage, reading-3`
- **2025-03-07T18:00:00+00:00** (H) Transmitted to Senate
- **2025-03-14T23:06:17+00:00** (S) First Reading `reading-1`
- **2025-03-14T23:32:00+00:00** (S) Referred to Committee - (S) Highways and Transportation `referral-committee`
- **2025-03-17T15:48:58+00:00** (S) Hearing - (S) Highways and Transportation
- **2025-03-19T22:30:01+00:00** (S) Committee Executive Action--Bill Concurred - (S) Highways and Transportation
- **2025-03-20T21:30:00+00:00** (S) Committee Report--Bill Concurred - (S) Highways and Transportation
- **2025-03-20T21:31:00+00:00** (S) Rereferred to Committee - (S) Highways and Transportation `referral-committee, referral-committee`
- **2025-03-24T22:01:40+00:00** (S) Committee Executive Action--Bill Concurred as Amended - (S) Highways and Transportation
- **2025-03-25T19:43:00+00:00** (S) Committee Report--Bill Concurred as Amended - (S) Highways and Transportation
- **2025-04-02T19:00:00+00:00** (S) Scheduled for 2nd Reading `reading-2`
- **2025-04-02T21:36:00+00:00** (S) 2nd Reading Concurred `reading-2, reading-2`
- **2025-04-03T19:00:00+00:00** (S) Scheduled for 3rd Reading `reading-3`
- **2025-04-03T19:36:00+00:00** (S) 3rd Reading Concurred `passage, reading-3`
- **2025-04-03T21:27:52+00:00** (S) Returned to House with Amendments
- **2025-04-16T19:00:00+00:00** (H) Scheduled for 2nd Reading `reading-2`
- **2025-04-16T20:33:00+00:00** (H) 2nd Reading Senate Amendments Concurred `amendment-amendment, amendment-passage, reading-2, reading-2`
- **2025-04-17T19:00:00+00:00** (H) Scheduled for 3rd Reading `reading-3`
- **2025-04-17T22:00:00+00:00** (H) 3rd Reading Passed as Amended by Senate `passage, passage, reading-3, reading-3`
- **2025-04-18T20:02:19+00:00** (H) Sent to Enrolling
- **2025-04-23T14:07:40+00:00** (H) Returned from Enrolling
- **2025-05-02T17:00:20+00:00** (H) Signed by Speaker `passage`
- **2025-05-06T20:00:07+00:00** (S) Signed by President `passage`
- **2025-05-07T15:03:52+00:00** (H) Transmitted to Governor `executive-receipt`
- **2025-05-13T18:51:00+00:00** (H) Signed by Governor `executive-signature`
- **2025-05-19T22:27:02+00:00** Chapter Number Assigned `became-law`

## Source

OpenStates / OpenCivicData bulk snapshot [2026-07-01](https://data.openstates.org/daily/2026-07-01/public.pgdump); origin `ocd-bill/6a05e890-669d-4bc1-8c8f-966cabf2495f`. Confidence: reported (aggregated from official Montana legislature records).