Spyware, to spy or not to spy!

Can a husband or wife install spyware on the other spouse’s phone or computer? You can certainly keep and use text messages or voicemails or even Facebook posts from the other party, but intercepting and saving communications that were intended for the other party is a first degree misdemeanor in Florida for the first offense, and a 3rd degree felony for subsequent offenses if for commercial gain or destruction. In other cases, it is a second degree misdemeanor. Read the statute below for thinking about planting spyware.
http://www.leg.state.fl.us/Statutes/index.cfm?App_mode=Display_Statute&Search_String=&URL=0900-0999/0934/Sections/0934.21.html
http://www.abajournal.com/news/article/judge_sends_sheriff_to_seize_hubbys_devices_after_spyware_is_found_on_wifes