code: function readSharedPolicy ({ id }, cb) {
        let promise = null
        if (typeof cb !== 'function') [promise, cb] = asyncify()
  
        Joi.validate({ id }, validationRules.readSharedPolicy, function (err) {
          if (err) return cb(Boom.badRequest(err))
  
          const sqlQuery = SQL`
            SELECT  *
            FROM policies
            WHERE id = ${id}
            AND org_id IS NULL
          `
          db.query(sqlQuery, function (err, result) {
            if (err) return cb(Boom.badImplementation(err))
            if (result.rowCount === 0) return cb(Boom.notFound())
  
            return cb(null, mapping.policy(result.rows[0]))
          })
        })
  
        return promise
      }
docs: fetch specific shared policy
  
  @param  {Object}   params { id }
  @param  {Function} cb