A top Brisbane law firm partner who filed false time sheets to swindle more than $515,000 from clients has been fined $20,000 but has not been banned from practising.

Luke James McDonald, a solicitor specialising in planning and environmental law, started adding false hours to 914 electronic time sheets in 2012 and within 18 months had scammed 23 clients.

Justice Tim Carmody said McDonald’s conduct demonstrated a deplorable lack of discipline and although no criminal charges will be laid all rorted clients have been repaid with interest by the firm for which he worked.