CHICAGO (CBS) — A bombing defendant is painting his own self-portrait on the witness stand in federal court.

As WBBM Newsradio’s John Cody reports, John Tomkins, 47, of Iowa, is representing himself in his trial on charges that he sent letters and dud pipe bombs to investment advisers.

LISTEN: WBBM Newsradio’s John Cody reports

He told jurors in closing arguments that he is far more than just a rural relief mail carrier. He is a skilled machinist, union secretary-treasurer, stock car driver and builder, and attendant father.

Tomkins admits he sent threatening letters signed “The Bishop” to Chicago investment companies, but he argues that he should not be convicted of the far more serious charge – a 30-year charge – of mailing bombs.

“He mailed threatening letters,” said Tomkins, referring to himself in the third person. “Hold him accountable for what he did.”

He argues the bombs he sent were not hooked up, and he could easily have activated them if he had wanted to.

The government alleges Tomkins wanted investment houses to raise the price of stock he owned in two technology firms.

Prosecutors allege Tomkins sent letters from 2005 until 2007 that threatened to kill those who received them, their families and neighbors unless they took action to raise the stock prices of 3COM Corp. and Navarre Corp., in which Tomkins had invested. They allege he mailed the pipe bombs from a suburban Chicago post office in 2007.

Tomkins, who Assistant U.S. Attorney Patrick Pope said identified himself in some of the letters as “The Bishop,” allegedly taunted the people who received them.

“Bang, you’re dead,” Pope quoted from one of the letters that accompanied a pipe bomb during his opening argument. “The only reason you’re alive is that I did not attach one wire.”

Prosecutors said the pipe bombs were real and would have detonated had all the wires been attached. Pope said the letters included a threat that the advisers better drive up the stock prices by a deadline he gave them or he would send more bombs, making sure to “connect all the wires,” before ending with the words “Tick, tock” or “Time’s up.”

(TM and © Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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