Hello Alexander,
Spanish lawyers do have an indemnity insurance. My only knowledge of anything (somewhat remotely) about this is as follows.

The original lawyers recommended by the EA we used has had so many complaints made about them to the Collegio de Abogados that their (lawyers) insurance company worked alongside the Collegio to carry out an investigation of this company. Apparently, as a result of this investigation the senior partner was suspended. He had the right to appeal...once. He lost that appeal but he appealed again and is still in practice

We, with the help of our lawyer and the Collegio, are now actively taking steps to recover the balance of money owed to us(approx 5.000euros) for a "no build" situation. They kept over 7,000 euros for just signing the contract. That?s as far as our purchase got. We are not holding out too great an expectation as the person from whom I got the above information has been waiting for 2 1/2 years for a settlement of their case against these lawyers.
Thanks a lot