Power corrupts.

These two words constitute the heart of the idea of democracy.

The people who invented America, on Chestnut Street, designed a government more out of fear of the potential harm of concentrated power rather than out of hope about an "efficient" government.

And almost immediately after they designed the checks and balances of our formal government institutions, they also created political parties. They understood that truly competitive elections, resulting in one party in power and another in loyal but skeptical opposition, are absolutely critical to avoiding the corruption of power.

How ironic it is, then, that Philadelphia, the birthplace of these ideas in the modern world, is the home to, and seems to be becoming numb to, routine scandal, and corruption among our elected officials. The latest example is the recent mind-boggling indictment of Philadelphia's highest-elected law-enforcement officer, District Attorney Seth Williams.

Neither Democrats nor Republicans are inherently corrupt, nor inherently more corrupt than one another. But any time, and any place, that those in power are unchallenged and unaccountable, especially for long periods of time, the situation feeds the worst impulses of human nature. Always has, always will.

Philadelphia has been virtually a one-party city since the 1950s. Even when a person of high integrity, such as Lynne Abraham, wins election, as a Democrat, to the job of district attorney, she can't really "fight City Hall." Why? Because she was on the same team as the people who ran City Hall.

Abraham, who hired me as prosecutor and whom I consider a mentor, formally recognized this and declined to prosecute public corruption cases. Instead, she deferred them to the state Attorney General's Office or the U.S. attorney. She rightly understood that there was, at an absolute minimum, an appearance of conflict of interest for her to be on a party ticket with someone one day and then investigating and perhaps prosecuting that same someone for corruption the next day.

That's partly why I am proudly running as the only Republican candidate for district attorney against the seven Democrats who are campaigning for the office. After the recent federal indictment of Williams - and the convictions in recent years of numerous Democratic public officials from Philadelphia - the answer to a cleaner city government isn't, and simply can't be, the election of a different Democrat. Remember, Williams ran on an anti-corruption platform and criticized Abraham for being soft on the misdeeds of other officials.

I was never political, much less partisan. Simply put, I was a public servant, a taxpayer, and a Philadelphian. But this city's recent tsunami of political corruption has inspired me to try and help my city do better. As a result, I have chosen to run for district attorney. And I have chosen to run as a Republican because this city, our city, deserves the true successful workings of self-government - which cannot and should not be selfish, self-serving, and self-dealing.

I served as an assistant district attorney for more than 21 years, working in nearly every unit in that office. I tried, and know that I often succeeded, in ensuring that criminals in Philadelphia were properly punished, that victims were properly respected, and that public nuisances, which damage the quality of life of ordinary people in every neighborhood, were properly redressed.

It is time for political balance in Philadelphia. It is time for change.

Beth Grossman is running unopposed in the Republican primary for Philadelphia district attorney. grossman.beth999@gmail.com