11:30 AM PT -- A rep for PETA tells TMZ ... "Anyone who encourages dogs to rip apart other animals should be in jail for cruelty to animals, not on a stage. Unless Will Moseley has changed and gained some much-needed compassion since his boar-killing days, PETA urges the public to vote according to their values and end his American Idol dream, the same way he ended the lives of vulnerable animals."

An "American Idol" contestant is getting dragged for an old video he posted that shows him on a hunt ... during which he seems to have sicced multiple dogs on a helpless hog.

Will Moseley -- a Top 8 finalist on the current season of 'AI' -- hasn't shied away from his hunting background in Georgia, where he's from ... and where he and his family appear to hit the woods pretty often to take down small game.

His father, Todd Moseley, has tons of photos of the two of them posing with dead wild hogs -- which they proudly put on display. We did some digging, and it looks like hog hunting like this is legal in Georgia -- with certain restrictions ... including permits, times of year, etc.

Regardless of that, people are up in arms over a clip from a couple years back that's disturbing to some. The video in question was thrown up in early '22 ... with Will's caption as, "Those good ol’ January Swims." He's posing with his dad and his girlfriend, Ryleigh.

The 3 of them are seen smiling over the corpse of a hog that appears to be the same one attacked on video -- which Will also posted ... and which is absolutely brutal. The animal can be seen cornered in a stream out in the wilderness, where a pack of dogs with Will and co. go on the attack.

Like we said ... even if perfectly legal in Georgia, which this appears to be, there's still a lot of outrage.

Folks are flooding Will's IG comments on this post, calling him out for what they perceive as animal cruelty -- with many denouncing his 'Idol' run, which is going quite well right now.

Considering how far he's come on the competition show, it's safe to say he's been a fan fave to this point.

However, this video of the dogs and hog is hard to watch -- and it's forcing some to give Will and his family a bit of side-eye. We've reached out to Will and 'Idol' ... no word back.

A rep for the Georgia Dept. of Natural Resources' Wildlife Resources Division tells TMZ ... "Hunting feral hogs -- an invasive species -- is allowed on private lands and, where and when designated, some public lands in Georgia. Where designated, dogs can be used in hunting feral hogs. There are no restrictions on that use except on public lands."