Unity Error Code

using UnityEngine;
using System.Collections;
using LitJson;
using System.Collections.Generic;
using System.IO;

public class ItemDatabase : MonoBehaviour {

    private List<Item> database = new List<Item>();    //Lists the items
    private JsonData itemData;                      //Grabbing items from json

    void Start()
    {
        //WHERE THE VALUES WILL BE STORED
        itemData = JsonMapper.ToObject(File.ReadAllText(Application.dataPath + "/StreamingAssets/Items.json"));  //Read the data from json
        ConstructItemDatabase();

        Debug.Log(database[1].Title);
    }

    public Item FetchItemByID(int id)
    {
        for (int i = 0; i < database.Count; i++)
            if (database[i].ID  == id)
                return database[i];
        return null;
    }

    void ConstructItemDatabase()
    {
        for (int i = 0; i < itemData.Count; i++)
        {
            //VALUES ADDED TO DATABASE
            database.Add(new Item((int)itemData [i]["id"], itemData[i]["title"].ToString(), (int)itemData[i]["value"],
                (int)itemData[i]["stats"]["damage"], (int)itemData[i]["stats"]["attackspeed"], (int)itemData[i]["stats"]["movespeed"], (int)itemData[i]["stats"]["defense"],
                (int)itemData[i]["stats"]["warmth"], itemData[i]["description"].ToString(), (bool)itemData[i]["stackable"], itemData[i]["slug"].ToString));
        }
    }

}


public class Item
{                       //VARIABLES THAT ALL ITEMS CAN USE
    private int ID{get; set;}               //ITEM ID THAT WILL BE USED TO IDENTIFY ITEMS
    public string Title {get; set;}         //NAME THAT WILL APPEAR IN-GAME
    public int Value { get; set;}           //STATES THE VALUE OF THE ITEM  EX. DIFFERENT COLORS
    public int Damage {get; set;}           //AMOUNT OF DAMAGE THE ITEM WILL DO TO ANOTHER OBJECT
    public int AttackSpeed {get; set;}      //HOW FAST THE ITEM GOES FROM IDLE ---> DEALING DAMAGE
    public int MoveSpeed {get; set;}        //THE SPEED OF THE CHARACTER WHILE MOVING WITH THE ITEM
    public int Defense {get; set;}          //AMOUNT OF DEFENSE THE ITEM PROTECTS THE CHARACTER WITH
    public int Warmth {get; set;}           //AMOUNT OF WARMTH THE CHARCTER RECIEVES WHILE HAVING THE ITEM
    public string Description {get; set;}   //DESCRIBES THE ITEM IN-GAME
    public bool Stackable {get; set;}       //BOOLEAN OF WHETHER THE ITEM IS STACKABLE OR NOT
    public string Slug {get; set;}


    public Item(int id, string title, int value, int damage, int attackspeed, int movespeed, int defense, int warmth, string description, bool stackable, string slug)
    {
        this.ID = id;
        this.Title = title;
        this.Value = value;
        this.Damage = damage;
        this.AttackSpeed = attackspeed;
        this.MoveSpeed = movespeed;
        this.Defense = defense;
        this.Warmth = Warmth;
        this.Description = description;
        this.Stackable = stackable;
        this.Slug = slug;
    }
    public Item()
    {
        this.ID = -1;       //INVALID ID CHECK
    }
}