Daniel L. Leyton has been rated "AV" by Martindale-Hubbell. According to Martindale-Hubbell
An AV® certification mark is a significant rating accomplishment - a testament to the fact that a lawyer's peers rank him or her at the highest level of professional excellence. A lawyer must be admitted to the bar for 10 years or more to receive an AV® rating.
An explanation of the ratings system is found here. Mr. Leyton's Martindale-Hubbell page is found here.