Trying to Detain a player and store that player's UserId?

I'm basically trying to create an arrest system where I can detain someone, drag them over to the vehicle backdoor, and use a keybind to either A.) place them in the car for transport or B.) teleport them straight to the jail.

I already have the detain from a freemodel script, I'm just having trouble storing the detained persons UserId.

local RemoteEvent = script.Parent:WaitForChild("RemoteEvent")
local TargetTorso = nil
local Using       = false


function CheckForTargetTorso(part)
    if part.Parent:IsA'Model' and part.Parent:FindFirstChildOfClass'Humanoid' then
        local char = part.Parent
        local torso
        if char:FindFirstChild'Torso' then
            torso = char.Torso
        elseif char:FindFirstChild'UpperTorso' then
            torso = char.UpperTorso
        end
        return char, torso
    end
end



function CheckForTorso(player)
    local Char = player.Character
    if Char:FindFirstChild'Torso' then
        return Char.Torso
    else 
        return Char.UpperTorso
    end
end


RemoteEvent.OnServerEvent:Connect(function(player, state, part)

    if state == 'Cuff' then
        local target      = nil
        local playerTorso = nil

        target, TargetTorso = CheckForTargetTorso(part)
        playerTorso = CheckForTorso(player)

        if target then
            Using = true
            RemoteEvent:FireClient(player, 'Use')
            spawn(function()
                if Using then
                    TargetTorso.Anchored = true         
                end             
                while Using and wait() do           
                    TargetTorso.CFrame = playerTorso.CFrame * CFrame.new( 0, 0, -5 )
                end             

            end)            

        end

    elseif state == 'UnCuff'then    
        Using = false       
        TargetTorso.Anchored = false
        wait()
    end

end)