Libertarian here and these are some of the solutions being discussed in our circles in regards to police brutality (the short version):
End qualified immunity. There is a bill being proposed to congress right now and you can read more about it here:
https://lpgeorgia.com/endqualifiedim...cQvtjEQvqDfBT4
I have already contacted my representatives to support this proposal.
Demilitarize the police.
Make officers pay for their own abuse settlements.
Prosecute police for civil rights violations.
If you want more in-dept information, I strongly suggest you check out Spike Cohen on Facebook. He is the Libertarian VP nominee and has had several REALLY GOOD live videos on his facebook page discussing these issues and tackling them from a libertarian prospective.
Also, since I am volunteering at a grassroots level for The Jo Jorgensen/Spike Cohen ticket check out the campaign page at Joj2020.com. Finally, Jo and Spike will be having an ask me anything facebook live event tonight from 5-6 EST on Jo Jorgensen's facebook. This would be a great opportunity to get answers straight from the candidates!