Push value in array and verify

I need to select distinct value and push them into an array. After that, i need to verify if a variable is situated into the array.

Controller:

$people = DB::table('checklists')->select('incaricato')->distinct()->get()->toArray();

if (in_array(\Auth::user()->id, $people)) {
    $variable = "yes";
}

Error:

Object of class stdClass could not be converted to int

via Chebli Mohamed