- Listen to what they've got. If they have a lot of stuff, listen to the earliest few submissions and then some newer ones. Then the most recent few. This is to check for growth. Does it sound like they started crummy, and gradually improved? If so, they're probably legit and may not need to prove their authorship. Usually you can safely scout an artist like this.
- Do a Google Sound Search, Shazam or in some cases, SoundHound on their audio. You might be able to pick up stolen stuff instead of troubling yourself with a song thief. Best to do this with good speakers, not crappy laptop speakers.
- Look around for similarly named remixes on YouTube. It might be a stolen remix.
- If you don't think they're good enough, leave at least a couple of constructive reviews. At least you'll be helping them to improve. Don't just tell them they're not good enough.
- Ask them how long they've been making music. Some artists on Newgrounds have been at it for over a decade and are indeed very good. In the case of some unscouted users, they will be well established on YouTube and want to provide download links for their songs or gather a new audience, only to find out about the scouting process.
- If they're very popular on YouTube or SoundCloud, snoop around a bit. It might be a poser/thief on NG. If only the most popular songs have been uploaded, you might have found a song thief posing as a popular artist. Contact a moderator about any scenario like this either through a PM or post about it on the Audio Portal Cleanup Thread. Note that popular people like this are already established and usually won't create an account on Newgrounds. Some have, but it doesn't happen often.
- Ask for more music from them, especially if you believe that they are uploading content that doesn't belong to them. This could reveal a stolen song you recognize.
- Contact a moderator if you believe they're not legit. It is the moderators' job to check out the legitimacy of possible poser accounts.
- Recommend or scout a user because their stuff is amazing. It might be stolen.
- Recommended or scout a user because they asked for a scout, for the same reason, or because they might not be good at all. If they're begging to be scouted, it's possible they're just trying to get stolen songs on Geometry Dash. Songs need to be downloadable in order to be used in Geometry Dash. You'll notice that the "Download This Song!" button is not present on any unscouted audio.
- Ask for a project file or other burden of proof. This is a moderator's job. However, if they already have a "making of" video on YouTube, you may take that into account when trying to determine authenticity.
- Continue to try to work with someone who's giving you attitude or thinks you're an asshole because you won't scout them. These kind of people aren't mature enough for the audio portal or interaction with the general public. They'll make Newgrounds look bad.
- Scout someone who is well established elsewhere without confirmation from moderators. If they're popular on YouTube or SoundCloud and start uploading to Newgrounds, it might be a song thief posing as said popular YouTuber/SoundCloud user.
- Scout someone who has only uploaded remixes. NG is for original works! Also, a user who makes shit tons of remixes is likely to break (or have broken) at least one of four rules in the audio portal - stolen songs, remixes/covers of music represented by a major record label, midi ripping or use of copyrighted sounds, such as vocals or instrumentals.
- Tell them straight up that they suck. That's not cool.