One of the many reasons that shutters make an ideal window dressing solution is because they are a more secure option to dress windows than blinds or curtains by being securely fixed around the whole space.
Exactly how secure any particular set of shutters are is dependent on multiple factors including the material that is selected and any added extras on the panels. There are numerous different variations to this as it depends on certain selections including material choices and potential extras such as locks or bolts that can be added to panels.
Plantation Shutters create an additional layer on windows so naturally act as more of a deterrent barrier because of their fixed coverage of the window area. This is more so the case than for other window dressings as blinds and curtains tend to only be attached to window areas at the top so do not have the same barrier levels.
Whilst the fixing of shutter frames and panels to windows can create more of a deterrent to the entry of window spaces, regular shutters are not in themselves a security measure. The protections that the shutters provide can be enhanced by the addition of locks, bolts or catches.