The union representing carpenters has some of the most aggressive picket lines in the country. But the picketers often aren't union members. Many are homeless.

The union calls them temporary workers, and the job pays eight dollars an hour. The picketers are often recruited at homeless shelters or transitional houses.

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The protests target office buildings where construction is being done without union labor.

The picketers hold placards and chant about low wages. They're often heard calling, "What do we want? Fair wages. When do we want them? Now."

Unions are divided over the practice. Supporters say it's an informational picket and a legitimate tool. Critics like the United Steelworkers of America say it doesn't create a very positive impression of union organizing.

Some say the money could be better spent on job training for the homeless. But William Strange says his work picketing helped him get a job and his own apartment.