EAST SIDE, west side, all around the town – there are 403 "authorized parking" spaces to turn frowns upside down. They are reserved, park-for-free spaces approved by the Managing Director's Office, mostly in Center City.

But then there are some that have not been approved, and how they got placed is a mystery. We'll play Sherlock Holmes together in a moment.

First, have you ever wondered who gets "authorized parking," and why?

I have.

"Request for a designation comes into the MDO (Managing Director's Office)," I'm told by First Deputy to the Managing Director David Wilson. Requests usually come from senior level people.

"The request is researched, impacted departments are consulted and a decision is made," he says. The process takes somewhere between weeks and months.

The managing director's office's "authorized" designations "involve on-street parking for city vehicles, employees, elected officials and media parking," Wilson says, although media gets "press parking" signs.

There is no written criteria.

A number of factors are taken into account, he says, including "impact to the current and future parking zone; impact to businesses and neighborhoods."

Also reviewed are current parking regulations, such as for handicapped persons, loading zones, meters, etc.

Once a request clears all hurdles, "the Streets Department installs the signage," says Streets Commissioner David Perri. "We have our own sign shop and make up signs ourselves from sheet metal stock."

Now we come to an "authorized parking" zone big enough for maybe a half-dozen cars in the 1800 block of Spring Garden.

That "authorized" space happens to be outside the headquarters of Metropolitan Regional Council of Carpenters.

"The signs at 1800 Spring Garden are not Streets Department-installed signs," says Perri. "We also checked with PPA (Philadelphia Parking Authority) and they did not install them. We have no idea who installed the signs."

The managing director's office "has no record of a request or decision that issued an authorized parking designation" at that location, says Wilson.

If the signage wasn't put up by Streets, Wilson says, "we are not clear on who installed the signs."

Well, isn't this a first-class mystery.

Since the signs are outside his hall, I call Carpenters Union honcho Edward Coryell.

My call was returned by union maintenance supervisor John Rowan, who told me the unauthorized "authorized parking" signs were already posted when the carpenters moved in around 15 years ago. Perri agrees.

They are attached to unauthorized, non-city poles, I am told by Wilson. Someone had a busy afternoon a long time ago.

To wrap it up, Streets told the property manager to take down the signs within a week, and the parking authority will decide what legal signs are to go up.

The mystery of how they got up in the first place is unresolved.

The signs were illegal and had to come down. It's a better city when we all play by the rules.

That goes for everything - illegal signs, people who don't clean up after their dogs, cafes that grab too much of the sidewalk, litterbugs, people who enter the country without legal permission, auto speeders and bicyclists who run red lights, among others.

You know, the selfish stuff I'd like to eliminate to make Philly a better place to live.

Phone: 215-854-5977

On Twitter: @StuBykofsky

Blog: ph.ly/Byko

Columns: ph.ly/StuBykofsky