I was a bit disappointed to learn that the Music Policies tool has been discontinued; if you now go to the page to check for music that you might be able to use without copyright strikes, it will result in a 404 error page.
If I am not mistaken, it was also not completely clear whether you could actually use the music listed by this tool, without the risk of getting sued. A copyright owner might also decide to change their stance, and I am not sure what would happen under such circumstances; would the track be silenced in our video? Would we get a copyright strike?
Obviously copyright owners should not be able to change their settings, and destroy people's videos in the process.
The music policies tool used to be available at:
YouTube removed the Music Policies tool
This may be a problem for people who are trying to know about the Copyright Holder's stance towards using their music for various purposes.
For example, it is very common for churches to upload cover versions of worship songs to YouTube, and many of them probably do not fully understand the copyright implications. What happens if a cover gets more popular than the original?
I had an e-mail correspondence with a fellow from my own church, who was managing the official worship channel of the church, and he did not believe this tool was sufficient to check if cover versions of a song was allowed.
The conclusion, at the time, was that you could still risk getting sued by the copyright holder.
Obtaining permission from the copyright holder
There is still the music library where you can find songs that can be legally used in your videos.
But, the problem apparently still remains; if you want to use a specific song, not listed in the library, you should contact the copyright owner directly, manually, and get a custom permission to use the song. There seems to be no automated system in place to manage licensing and permissions.
A centralized place to handle and obtain licenses for music would be much more useful. Micromanaging copyright issues is not sustainable; but maybe the problem is not with YouTube, but rather an ancient copyright system that refuses to adapt.