Inside Report (3)

Massachusetts tax accountants should be blushing.

Since 1971 a state law has allowed eligible businesses to take a 3 percent investment tax credit - and nobody has ever used it. The law, of particular interest to companies renting property from community development corporations, was rediscovered several weeks ago by the Boston Private Industry Council.

''It's never been a secret,'' says council official Kathleen Tullberg, who thinks it will be helpful in attracting new businesses into the state. But it does bolster her view that ''most businessmen don't have adequate information'' even on familiar programs.m