The concept of civil liberty is generally misused. It is largely used by selfish people to justify doing whatever they like, regardless of the harm they cause. It is worth remembering that one person's liberty is almost always to the detriment of someone else's liberty. Therefore a balance always has to be found. It is where you draw the line.
For example, civil liberty is wrongly used to defend smoking. Those who argue this don't care about the 'civil liberties' of people who want to be able to enjoy going where they like, without having to breath smoke and damage their health. When it becomes a health and safety issue, the health of the non-smoker should be more important than the rights of the addicted.
When somebody uses civil liberties in support of their argument, ask critically for evidence to back up what they say. As AC Grayling puts it;
"A familiar but profound fact explains the vexed character of moral, social and political debates, namely, that there are almost always at least two diametrically different ways of seeing the same human problem. People appeal to their principles, their traditions, their rights and the threat to all three, in justifying what to outsiders seems to be their obduracy, pig-headedness and prejudice. Moral skill is the ability to distinguish which is which."
n.b. I agree with most of Grayling's linked article but I disagree that ID cards are an attack on civil liberties, as demonstrated by the numerous liberal countries that have them.