Problem is with that is it is computer driven. The practice management software records the time you are on the phone with them and automatically adds it to your bill. Always open on your desktop is the practice management software, so when you are working on a matter you have a client field for the account name and a start/finish and a pause button which times all the work stuff. However with the higher end software it is linked to the phone system so when you are put through it starts timing for your account and stops when it hangs up, you can also set it to automatically record the conversation and it saves as an mp3 in the clients file. Expensive software but pays for itself with reduced time spent on logging billing.
If the lawyer works for a decent sized firm they will also have to meet minimum billing time. The nicer ones might let you get away with billing 5.5hrs per day, the not so nice (though better paying ones) want you to bill 7.5 hrs per day and that is actual billable hours not time on site. You may also be required to average that over the year for 5 days a week. So if you take your 4 weeks annual leave and have to do the 7.5 hrs a day that's 150 hours of billing time you need to make up. And unless you are senior you probably don't get a share in that either, it's jsut what you are required to do to make salary, albeit a decent one.
I have done a fair bit of research on this as I should be opening a property law and property accounting firm in inner Brisbane with my partners in the second half of this year. We are going to run a completely different model where the lawyers and accountants get no salary at all, they receive a % of their billable hours/ fees. This way we are aiming to attract driven professionals who don't want the staffing hassles of running a firm/partner advertising etc. As always can't give too much info at this stage as my partners are involved with other practices at present and will not be making it paublic until thier notice is given.