Here's one more thing to blame on Congress.

Although the battle over extending a Social Security payroll tax reduction continues in Washington, D.C., the matter has already been settled for California state workers: They'll have more money withheld from their checks next month, no matter what.

It's a matter of timing.

Congress has been arguing for weeks over the particulars of extending a lower Social Security tax rate set to expire Dec. 31. Unless lawmakers cut a deal, the reduced 4.2 percent tax that has been in effect since Jan. 1 will increase to the former 6.2 percent rate.

There's talk that Congress might still extend the lower rate even though many members are on recess, but even if it acted today, it's too late for California state workers' Jan. 1 paychecks.

The controller's office is already calculating their December wages at the higher tax rate, which translates into $2 more withheld for every $100 earned.

Paying state employees isn't like paying your bills with Quicken. Last month the controller issued 136,450 warrants and 307,265 direct deposits totaling $1.53 billion in gross wages.

The state uses a system that calculates those wages about 10 days before the end of each monthly pay period. The checks and direct deposits issued on the first day of each month don't include pay changes that happen after that.

Tuesday was the deadline to submit state payroll changes. Anything from Wednesday through Dec. 31 that affects pay – unexpected overtime, say, or 11th-hour tax withholding changes enacted by a bickering Congress – will be figured along with the January wages that go into the checks issued Feb. 1.

Controller John Chiang's payroll division chief, Lisa Crowe, sent a letter to state agencies on Tuesday, telling them the IRS had "prescribed 6.2 percent as the Social Security tax rate to be paid by employees beginning with payrolls that are issued January 1, 2012."

Chiang spokesman Jacob Roper said the state's process isn't the problem.

"This has been caused by the inability of Congress to set policy in a timely manner," Roper said in a Wednesday interview.

If it turns out that lawmakers extend the tax break soon, the state will refund the difference on February's paycheck, Roper said.

State workers probably have one other question: If the lower tax rate doesn't expire until Dec. 31, why is the Jan. 1 state paycheck that covers December affected by the change?

The IRS instructions say the rate change affects state paychecks issued on Jan. 1.

The same thing happened when the rate was reduced: The Jan. 1, 2010, checks reflected the 2 percentage point tax decrease. In other words, state employees have already received 12 months of pay at the lower tax rate.

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Call The Bee's Jon Ortiz, (916) 321-1043. Read his blog, The State Worker, at sacbee.com/blogs.

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