There are several things to consider:
Where are you going? Are you leaving the country or staying in the country? Will they check liquids in checked baggage? Will they care if they find it?
First, yes, they can and do check liquids in checked luggage. Although larger quantities are allowed in your checked luggage they will still x-ray and inspect liquids contained in there. This is true even if your luggage is locked as all luggage have master keys/codes available to people working at these points. If you location a noncomplying lock on your case they will simply cut it off.
If they find vodka in a water bottle they will confiscate it and you could face charges related to smuggling. If, however, they find vodka in a vodka bottle the worst that will probably happen is confiscation and a lecture (assuming the bottle is still sealed).
If you are leaving the country and your bottle is discovered there then you may face other problems which could include deportation and a criminal record in that country. As such it could affect your ability to getaway in the future. Remember that simply because you do not get into serious trouble at property you will not have trouble in other locations. In some countries possession of alcohol can lead to prison time.
So, to summarize, yes you can get into trouble not just for possession of alcohol but for attempting to "smuggle" it. These days smuggling one thing can lead to problems in other areas. Who knows, you may end up on a "no fly" list.