I was once told by a retired FBI agent that if you had 3way calling on a land line & you pick the phone up and call yourself and it doesn't call you right back then someone is listening. Now mind you this was in the 90s so how relevant the information is, I don't know.
Not anymore.
Police/Governments can tap anyone as it desire only in case if you are a menace to the society or other things that make them want to tap your line.
as soon as they are interested in you......
No.
The police tap the phone of a suspected criminal even though they don't have a warrant.
It's illegal to do that anywhere!
In the US it requires a warrant to tap a phone line. But there are exceptions under the Patriot Act.
The police tap the phone of a suspected criminal without a warrant.
No you can not. Its the only mobile phone that you can not tap
Only if they have obtained a federal wiretap warrant from a federal judge.
no
So, tap "Menu" on your screen, and then tap "Settings and Tools". After that, tap "Phone Settings", and then tap "Security".