You've posted on a UK-based forum but the terminology in your question suggests that you're in the USA. (The UK and the USA use the term 'college' differently and we don't refer to 'majors' here).
In the UK people wanting to become social workers (irrespective of the specific field that they might eventually want to work in) would normally either
(a) take a 3-year (or 4-year) university course specifically in Social Work ; or
(b) study
any one subject for 3 (or 4) years at university and then go on to undertake a postgraduate course of study in Social Work.
(See here to view the approved courses available in this country:
https://www.hcpc-uk.org/education/approved-programmes/approved-programmes-results/?Professions=270450015&ProviderQueryString=&IntakeModes=Open ).
However the USA has got a very different eduction system from that in the UK and it's likely that there will be differences in training for social work as well.
You're more likely to find people with knowledge of how the the system works in your country on a US-based Q&A website. Unfortunately most of them seem to be very poorly moderated and therefore full of trolls and spammers. (e.g. Yahoo Answers and Answerbag). However Quora might be worth a try:
https://www.quora.com/
This looks like it might help though:
https://www.mswguide.org/careers/criminal-justice-social-work/