But such security systems have not proved completely reliable, experts say.

The black channel had been installed only recently, and like all new technology it was not completely reliable.

See, the path shown on a message isn't completely reliable.

I called in one of our medical staff several days ago - he's completely reliable.

He is still very young, and not always completely reliable.

A few rules can be given, though these are not completely reliable.

This was the first diagnosis technique available, but is not completely reliable.

Is evidence completely reliable when a person charged with a crime might be expected to say anything to reduce a potential sentence?

The F1 had many problems and was not completely reliable.

Someone strong and completely reliable, including able to keep his mouth shut.