No benefit to hands-free phone

New study:

(CNN) -- A study released Tuesday said drivers who use cell phones -- even hands-free models -- are four times as likely to be involved in wrecks involving a serious injury than are drivers who do not use cell phones.

"There was no safety benefit whatsoever from using a hands-free phone," said Anne McCartt, one of the authors of the study, which was published in the British Medical Journal and paid for by the Insurance Institute for Highway Safety.

So all the cities and states passing hands-free phone use laws may not be making anyone safer.